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== Origins  ==
 
== Origins  ==
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n the early 1970s there was a group of five academic staff in the School eager to learn more about particle-solid interactions. They had by then equipped themselves intellectually and with the machines of experimental physics to carry out research in this field in a systematic way with projects that would fill in gaps in current knowledge. Around them students had clustered who were learning how to carry out research and enlarging their own understanding of the physical sciences. These students were attending lectures, reading and carrying out original experiments. The group had attracted postdoctoral fellows pursuing the more advanced topics and distinguished academic visitors, often from overseas, wishing to gain experience at Sussex and, perhaps, to build collaborative projects with their own groups. Altogether there were about 30 people involved in the group at any time in the mid 1970s.
  
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In the early 1970s there was a group of five academic staff in the School eager to learn more about particle-solid interactions. They had by then equipped themselves intellectually and with the machines of experimental physics to carry out research in this field in a systematic way with projects that would fill in gaps in current knowledge. Around them students had clustered who were learning how to carry out research and enlarging their own understanding of the physical sciences. These students were attending lectures, reading and carrying out original experiments. The group had attracted postdoctoral fellows pursuing the more advanced topics and distinguished academic visitors, often from overseas, wishing to gain experience at Sussex and, perhaps, to build collaborative projects with their own groups. Altogether there were about 30 people involved in the group at any time in the mid 1970s.  
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A decade earlier four of these five were themselves postdoctoral fellows doing advanced research overseas alongside leading scientists of the day. To name them, Derek Palmer was in the Ecole Normale Supérieure, Paris, Mike Lucas was in the Argonne National Laboratory in Illinois, John Venables was in the University of Illinois at Urbana and Peter Townsend was in the Brookhaven National Laboratory in New York State. The fifth man was Michael Thompson, occasionally to be found visiting these labs and others like them, sometimes extending his visits over many months to engage in collaborative research. His first job after graduating in 1953 had been in the Atomic Energy Research Establishment at Harwell, but then in 1965 he was appointed to a Chair of Experimental Physics in Sussex. At Sussex he was warmly welcomed by John Venables, who had earlier returned from Illinois to a Lectureship in Physics, and by Robert Cahn who had been appointed to the Chair of Materials Science in the School of Applied Sciences and had himself worked in Harwell.
  
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A decade earlier four of these five were themselves postdoctoral fellows doing advanced research overseas alongside leading scientists of the day. To name them, Derek Palmer was in the University of Paris, Mike Lucas was in the Argonne National Laboratory in Illinois, John Venables was in the University of Illinois at Urbana and Peter Townsend was in the Brookhaven National Laboratory in New York State. The fifth man was Michael Thompson, occasionally to be found visiting these labs and others like them, sometimes extending his visits over many months to engage in collaborative research. His first job after graduating in 1953 had been in the Atomic Energy Research Establishment at Harwell, but then in 1965 he was appointed to a Chair of Experimental Physics in Sussex. At Sussex he was warmly welcomed by John Venables, who had earlier returned from Illinois to a Lectureship in Physics, and by Robert Cahn who had been appointed to the Chair of Materials Science in the School of Applied Sciences and had himself worked in Harwell.  
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Another member joined the group shortly afterwards. His name was Barry Farmery and he had worked with Michael Thompson at Harwell in building accelerators and running experiments. At Sussex he became responsible for installing and operating the accelerators, managing a team of technicians, giving advice on the use of ion beams and frequently becoming involved as a respected collaborator in experiments.
  
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Another member joined the group shortly afterwards. His name was Barry Farmery and he had worked with Michael Thompson at Harwell in building accelerators and running experiments. At Sussex he became responsible for installing and operating the accelerators, managing a team of technicians, giving advice on the use of ion beams and frequently becoming involved as a respected collaborator in experiments.  
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The historical context of British science in the 1950s and 1960s is of relevance to this history because each member had graduated from a British university. After the Second World War the country had its ancient universities and it had the late-Victorian civic universities. All had increased in size only to the point where about 5% of pupils leaving school could go on to university education. The country in response to military needs had created vast establishments for research and development in aviation, jet propulsion, electronics, radar, chemical and biological weapons and atomic weapons. Besides this there were peaceful needs being met in large central laboratories, for example in medical research, telecommunication, public health and the newest was in atomic energy. To exploit discoveries many large industrial companies had their own research and development laboratories. By the mid 1950s the policies of the government were to shift some work from their own labs to those industries or, if the research was of a more fundamental kind, encourage the universities to take it on.  But if none of the three wished to fund a topic it would be closed down.
  
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The historical context of British science in the 1950s and 1960s is of relevance to this history because each member had graduated from a British university. After the second world war the country had its ancient universities and it had the late-Victorian civic universities. All had only increased in size to the point where almost 5% of pupils leaving school could go on to university education. The country in response to military needs had created vast establishments for research and development in aviation, jet propulsion, electronics, radar, chemical and biological weapons and atomic weapons. Besides this there were peaceful needs being met in large central laboratories, for example in medical research, telecommunication, public health and the newest was in atomic energy. To exploit discoveries many large industrial companies had their own research and development laboratories. By the mid 1950s the policies of the government were to shift some work from their own labs to those industries or, if the research was of a more fundamental kind, encourage the universities to take it on. But if none of the three wished to fund a topic it would be closed down.  
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The government had also recognised a shortage of university places, firstly because the wartime recruits into military service returned as civilians wishing to take up the higher education they had missed and secondly because of the wishes of school-leavers in a burgeoning population of young people. A committee of enquiry chaired by the eminent educationalist Lord Robbins recommended that higher education should be open to all with the ability to benefit from it. The implication was that the State would pay, in grants to the universities and grants to the students for their fees and maintenance. It was decided, momentously, to accept this doctrine, to expand existing universities and establish six new universities of which Sussex was one.  
  
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The government had also recognised a shortage of university places, firstly because the wartime recruits into military service returned as civilians wishing to take up the higher education they had missed and secondly because of the wishes of school-leavers in a burgeoning population of young people. A committee of enquiry chaired by the eminent educationalist Lord Robbins recommended that higher education should be open to all with the ability to benefit from it. The implication was that the State would pay, in grants to the universities and grants to the students for their fees and maintenance. It was decided, momentously, to accept this doctrine, to expand existing universities and establish six new universities of which Sussex was one.  
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The policy on government labs had meant for young graduates aspiring to research that places like Harwell would be less likely to employ them. On the other hand the British universities had been full. It had seemed that careers for young British scientists might better be pursued in America. Four of this group had already gone overseas to work and could well have stayed. The fifth was looking at an attractive US offer and wondering whether to emigrate.  But now the new university policy changed the prospect and the UK was on offer too. So it was that the group was enabled to form.
  
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The policy on government labs had meant for young graduates aspiring to research that places like Harwell would be less likely to employ them. On the other hand the British universities had been full. It had seemed that careers for young British scientists might better be pursued in America. Four of this group had already gone overseas to work and could well have stayed. The fifth was looking at an attractive US offer and wondering whether to emigrate. But now the new university policy changed the prospect and the UK was on offer too. So it was that the group was enabled to form.
 
  
 
== Themes  ==
 
== Themes  ==
  
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The group could have had several labels that included: ionising radiation in matter, or atomic collisions in solids, or radiation damage and defects in solids, to give but three examples. But to catch up as many themes as possible without writing a paragraph ‘Particle-Solid Interactions’ had to do and that was what the group called itself for a visit by an assessment panel of the Science Research Council in 1975.  
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The group could have had several labels that included: ionising radiation in matter, or atomic collisions in solids, or radiation damage and defects in solids, to give but three examples. But to catch up as many themes as possible without writing a paragraph ‘Particle-Solid Interactions’ had to do and that was what the group called itself for a visit by an assessment panel of the Science Research Council in 1975.
  
 
Some paragraphs follow in which the interests of the five members of the group are summarised. Each knew that he could not cover every aspect of knowledge in such a broadly defined field but would devise experiments and theories to fill interesting gaps in his own knowledge. If that gap might also be of interest to another member of the group it might be given priority, or collaboration might develop or a project might transfer from one member to another.  
 
Some paragraphs follow in which the interests of the five members of the group are summarised. Each knew that he could not cover every aspect of knowledge in such a broadly defined field but would devise experiments and theories to fill interesting gaps in his own knowledge. If that gap might also be of interest to another member of the group it might be given priority, or collaboration might develop or a project might transfer from one member to another.  
  
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The group united around a willingness to share interests, a desire to explore zones of scientific ignorance and to map them for others to follow. One way that unity found expression was in regular seminars attended by staff and students where someone would talk about the current state of their research and expect discussion. Whatever its breadth of interest the scope of the group’s research was limited by equipment, for it had built or purchased a set of tools that could serve some purposes but not others. The members also had options to use equipment elsewhere, but by 1975 it was unlikely that they could add much to those expensive resources. Their particle toolkit included two electron microscopes, a 20kV pulsed ion accelerator for heavy ions, a 300kV ion accelerator and a 3MV van de Graaf accelerator, for ions or electrons, housed in a specially shielded building. Later, a small 45kV ion implanter was added. This was followed in the 1990’s by a high current 200 kV implanter which was mostly used on a commercial project to explore changes in the surface properties of glass in areas as diverse as production of car mirrors, anti-reflective coatings and reflective sunglasses.  
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The group united around a willingness to share interests, a desire to explore zones of scientific ignorance and to map them for others to follow. One way that unity found expression was in regular seminars attended by staff and students where someone would talk about the current state of their research and expect discussion. Whatever its breadth of interest the scope of the group’s research was limited by equipment, for it had built or purchased a set of tools that could serve some purposes but not others. The members also had options to use equipment elsewhere, but by 1975 it was unlikely that they could add much to those expensive resources. Their particle toolkit included two electron microscopes, a 20kV pulsed ion accelerator for heavy ions, a 300kV ion accelerator and a 3MV van de Graaf accelerator, for ions or electrons, housed in a specially shielded building. Later, a small 45kV ion implanter was added. This was followed in the 1990’s by a high current 200 kV implanter which was mostly used on a commercial project to explore changes in the surface properties of glass in areas as diverse as production of car mirrors, anti-reflective coatings and reflective sunglasses.
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== Scientific Interests  ==
 
== Scientific Interests  ==
  
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The fundamental scientific question for the group was how are the structure and properties of condensed matter affected by an environment of ionising radiation? That question grows upon roots in the technologies of electronics, nuclear energy and medicine. Besides the intrinsic scientific value of the answers, applications were inferred that could benefit everyone.  
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The fundamental scientific question for the group was how are the structure and properties of condensed matter affected by an environment of ionising radiation? That question grows upon roots in the technologies of electronics, nuclear energy and medicine. Besides the intrinsic scientific value of the answers, applications were inferred that could benefit everyone.
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The impact of ions upon a surface in a vacuum has a bad history of spoiling the performance of electrical machines. For example vacuum devices like fluorescent tubes for lighting and electron tubes for television are spoiled by atoms being sputtered by ion impact from electrodes and condensing inside the tubes to prevent light from being emitted. The newer solid-state devices in electronics or power engineering are made of semiconductor crystals whose electrical conductivity is engineered by creating defects (eg. by adding minute concentrations of phosphorous to silicon to make a dilute alloy) But if the device is exposed to ionising radiation crystal defects may be created that could inhibit its performance. Paradoxically, ion impact can have effects that create technical opportunities. The bad guy appears to be good in processes for making modern microcircuits like sputtering, ion implantation and radiation damage.
  
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The impact of ions upon a surface in a vacuum has a bad history of spoiling the performance of electrical machines. For example vacuum devices like fluorescent tubes for lighting and electron tubes for television are spoiled by atoms being sputtered by ion impact from electrodes and condensing inside the tubes to prevent light from being emitted. The newer solid-state devices in electronics or power engineering are made of semiconductor crystals whose electrical conductivity is engineered by creating defects (eg. by adding minute concentrations of phosphorous to silicon to make a dilute alloy) But if the device is exposed to ionising radiation crystal defects may be created that could inhibit its performance. Paradoxically, ion impact can have effects that create technical opportunities. The bad guy appears to be good in processes for making modern microcircuits like sputtering, ion implantation and radiation damage.  
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In the development of nuclear energy for peaceful purposes it was soon discovered that the useful life of reactor materials is limited by radiation damage. In fission reactors fuel rods swell, ductile metals become brittle and by storing energy graphite moderators might unexpectedly overheat. Fusion reactors have similar problems but in addition atoms are sputtered by particle impact from their internal walls which may inhibit the desired fusion. In 2010 the technology of atomic energy still needs research into these effects as the third generation of fission reactors and the first generation of fusion reactors are being built.
  
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In the development of nuclear energy for peaceful purposes it was soon discovered that the useful life of reactor materials is limited by radiation damage. In fission reactors fuel rods swell, ductile metals become brittle and by storing energy graphite moderators might unexpectedly overheat. Fusion reactors get similar problems but in addition atoms are sputtered by particle impact from their internal walls which may inhibit the desired fusion. In 2010 the technology of atomic energy still needs research into these effects as the third generation of fission reactors and the first generation of fusion reactors is being built.  
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The early style of experimentation in nuclear science was to irradiate a sample with neutrons in a reactor and take this back to the lab for measurement or, with more difficulty, do the measurements inside the reactor. But at Harwell in 1958 a ground-breaking move had been made when a small accelerator of heavy ions was built to simulate irradiation by neutrons. Argon ions having energies of 50 keV bombarding a sample of copper will produce the same sort of atomic recoils as 2 MeV neutrons and the experiments become better controlled and easier to analyse. For example one could create damage in thin crystals that could be seen as disordered regions in an electron microscope. Or atoms sputtered from the crystal surface could have their distribution of energy analysed knowing that this carries information about collision cascades inside the irradiated solid.  
  
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The early style of experimentation in nuclear science was to irradiate a sample with neutrons in a reactor and take this back to the lab for measurement or, with more difficulty, do the measurements inside the reactor. But at Harwell in 1958 a ground-breaking move had been made when a small accelerator of heavy ions was built to simulate irradiation by neutrons. 50keV Ar+ ions bombarding a sample of copper will produce the same sort of atomic recoils in as 2MeV neutrons and the experiments become better controlled and easier to analyse. For example one could create damage in thin crystals that could be seen as disordered regions in an electron microscope. Or atoms sputtered from the crystal surface could have their distribution of energy analysed knowing that this carries information about collision cascades inside the irradiated solid.  
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In both semiconductors and metals many valuable experiments on radiation damage had been done in the 1950s and 60s with MeV electron beams from accelerators, but the new heavy ion accelerators opened a new door. In addition to damage to the structure they could also implant ions of another chemical element and a new way of making dilute alloys was invented. It had the attractive new feature of being able to implant to a depth that was controlled by the ion energy. Entirely new classes of electronic device followed, as did metal surfaces with increased resistance to wear.
  
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In both semiconductors and metals many valuable experiments on radiation damage had been done in the 1950s and 60s with MeV electron beams from accelerators, but the new heavy ion accelerators opened a new door. In addition to damage to the structure they could also implant ions of another chemical element and a new way of making dilute alloys was invented. It had the attractive new feature of being able to implant to a depth that was controlled by the ion energy, entirely new classes of electronic device followed, as did metal surfaces with increased resistance to wear.  
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When the group of five assembled in Sussex during the 1960s some of these things had just been done at the places they came from. But prospects were open and many ideas were left to be explored. To show how the mosaic of members’ interests made a picture and how the borders and gaps in that picture became places for conjecture or research, a brief summary of the achievements and interests of the five academic leaders follows below.
  
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When the group of five assembled in Sussex during the 1960s some of these things had just been done at the places they came from. But prospects were open and many ideas were left to be explored. To show how the mosaic of members’ interests made a picture and how the borders and gaps in that picture became places for conjecture or research, a brief summary of the achievements and interests of the five academic leaders follows below.  
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John Venables, who arrived in 1963, had contributed for some years to the study of crystal defects and crystal growth by the diffraction of an electron beam in an electron microscope. Because defects perturb the diffraction process the image of crystal in the microscope can show their position and may even allow their structures to be resolved. At high enough energies the electrons of the microscope beam can themselves produce radiation damage whose structures may be studied in the same instrument.  
  
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John Venables, who arrived in 1963,? had contributed for some years to the study of crystal defects and crystal growth by the diffraction of an electron beam in an electron microscope. Because defects perturb the diffraction process the image of crystal in the microscope can show their position and may even allow their structures to be resolved. At high enough energies the electrons of the microscope beam can themselves produce radiation damage whose structures may be studied in the same instrument.  
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It was a powerful technique and especially so because John Venables had modified his microscopes, uniquely, to permit the sample to be cooled to very low temperature, bombarded with low energy ions to create visible defects, or have vapours condensed upon it. Major contributions were being made by his students by 1975 to our understanding of the processes by which a vapour condenses into a crystalline film upon a crystalline substrate where, initially very thin mono-layers of atoms cover the entire surface then thicker islands form whose growth is fed by diffusion from the mono-layer.  
  
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It was a powerful technique and especially so because John Venables had modified his microscopes, uniquely, to permit the sample to be cooled to very low temperature, bombarded with low energy ions to create visible defects, or have vapours condensed upon it. Major contributions were being made by his students by 1975 to our understanding of the processes by which a vapour condenses into a crystalline film upon a crystalline substrate where, initially very thin mono-layers of atoms cover the entire surface then thicker islands form whose growth is fed by diffusion from the mono-layer. <br>(I hope John could amend or add some more here, especially microstructures from ion bombardment and electron damage)
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Michael Thompson arrived in 1965 having studied at Harwell the way in which the kinetic energy of a particle creates defects in the solid. It can do this through a cascade of atomic collisions spreading out from the point of impact or the ionisation around the particle track. A related effect is the kinetic sputtering of atoms through the surface that could be studied by measurement of their momentum. That is to say that one measures both the angular distribution and the energy distribution. A pulsed ion beam and a time-of flight apparatus had been devised for this purpose. Theoretical work on the statistics of collision cascades and the effect of the surface upon the emerging atoms led him in 1967 to a formula E/(E + Eb)3 for the energy distribution and this was being found in many experiments ( Eb is the binding energy of an atom to the surface). It is often referred to as the Thompson formula in the literature.  From the fact that the distribution becomes like 1/E2 when E >> Eb one infers that the number of atoms permanently displaced from their sites by a collision cascade must be proportional to the energy in the first collision. This is a result of great importance in radiation damage. Departures from this sputtering formula were being discovered in the case of very energetic and heavy ions or in the case of single-crystal targets. These were hot topics in 1975 that revealed the presence of literally hot spots around the site of the collision cascade, and showed how the crystal structure itself imposes structure upon the cascade.
  
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Michael Thompson arrived in 1965 having studied at Harwell the way in which the kinetic energy of a particle creates defects in the solid. It can do this through a cascade of atomic collisions spreading out from the point of impact or the ionisation around the particle track. A related effect is the kinetic sputtering of atoms through the surface that could be studied by measurement of their momentum. That is to say that one measures both the angular distribution and the energy distribution. A pulsed ion beam and a time-of flight apparatus had been devised for this purpose. Theoretical work on the statistics of collision cascades and the effect of the surface upon the emerging atoms led him in 1967 to a formula E/(E + E<sub>b</sub>)<sup>3</sup> for the energy distribution and this was being found in many experiments ( E<sub>b</sub> is the binding energy of an atom to the surface). It is often referred to as the Thompson formula in the literature. From the fact that the distribution becomes like 1/E<sup>2</sup> when E &gt;&gt; Eb one infers that the number of atoms permanently displaced from their sites by a collision cascade must be proportional to the energy in the first collision. This is a result if great importance in radiation damage. Departures from this sputtering formula were being discovered in the case of very energetic and heavy ions or in the case of single-crystal targets. These were hot topics in 1975 that revealed the presence of literally hot spots around the site of the collision cascade, and showed how the crystal structure itself imposes structure upon the cascade.
 
  
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<br>In the early 1960s a related phenomenon had been discovered called channelling. In this a particle entering a crystal in a direction close to a prominent crystal axis and on a trajectory that entered the surface in the spaces between the atomic rows that define that axis, travelled long distances bouncing back and forth amongst those rows. It was manifested by exceptional ranges of ions of any mass when their beams were aligned within some critical angle of an axis. This angle was typically a few degrees and proportional to [Z1Z2/E]1/2 , here Z1 and Z2 are the atomic numbers of particle and solid respectively and E is the particle’s kinetic energy. The penetration experiments with light ions had been done at Harwell by Michael Thompson and his colleagues, the heavy ion penetration by a Canadian group led by John A Davies and the theory of the critical angle came from Denmark’s Jens Lindhard. The effect of channelling was also seen in the reflection or back-scattering of ions where minima were seen in the reflected fraction of the beam whenever the beam was aligned with either rows or planes. There was then both axial and planar channelling and many groups entered into the study of this phenomenon and its applications. High energy electrons and positrons were joined in too.  
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In the early 1960s a related phenomenon had been discovered called channelling. In this a particle entering a crystal in a direction close to a prominent crystal axis and on a trajectory that entered the surface in the spaces between the atomic rows that define that axis, travelled long distances bouncing back and forth amongst those rows. It was manifested by exceptional ranges of ions of any mass when their beams were aligned within some critical angle of an axis. This angle was typically a few degrees and proportional to [Z1Z2/E]1/2 , here Z1 and Z2 are the atomic numbers of particle and solid respectively and E is the particle’s kinetic energy. The penetration experiments with light ions had been done at Harwell by Michael Thompson and his colleagues, the heavy ion penetration by a Canadian group led by John A Davies and the theory of the critical angle came from Denmark’s Jens Lindhard. The effect of channelling was also seen in the reflection or back-scattering of ions where minima were seen in the reflected fraction of the beam whenever the beam was aligned with either rows or planes. There was then both axial and planar channelling and many groups entered into the study of this phenomenon and its applications. High energy electrons and positrons were joined in too.
  
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In a side-shoot of this field Michael Thompson had scattered ions at grazing incidence from the flat surface of a crystal whilst on a visit to Canada. A significant number were reflected as if by a mirror – the ion’s momentum perpendicular to the surface being reversed -. His students were studying this process further and devising means by which the structure and composition of surfaces could be determined. The theory of channelling was also to be refined by these observations and linked to experiments, about to be described, by one of Derek Palmer’s students.  
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In a side-shoot of this field Michael Thompson had scattered ions at grazing incidence from the flat surface of a crystal whilst on a visit to Canada. A significant number were reflected as if by a mirror – the ion’s momentum perpendicular to the surface being reversed -. His students were studying this process further and devising means by which the structure and composition of surfaces could be determined. The theory of channelling was also to be refined by these observations and linked to experiments, about to be described, by one of Derek Palmer’s students.
  
 
Michael Thompson’s interest in the penetration of heavy ions into the solid was being pursued in 1975 by a student measuring the distribution of depths below the surface at which these ions lodged. The method used was to back-scatter MeV H+ or He+ ions into an energy sensitive detector and from their energy distribution unfold the depth distribution. The species of heavy ion was varied, or the kinetic energy, or the angle of incidence. From the data of many such experiments it was hoped to test and refine theories current at that time or at least provide empirical data for technology.  
 
Michael Thompson’s interest in the penetration of heavy ions into the solid was being pursued in 1975 by a student measuring the distribution of depths below the surface at which these ions lodged. The method used was to back-scatter MeV H+ or He+ ions into an energy sensitive detector and from their energy distribution unfold the depth distribution. The species of heavy ion was varied, or the kinetic energy, or the angle of incidence. From the data of many such experiments it was hoped to test and refine theories current at that time or at least provide empirical data for technology.  
  
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Derek Palmer’s interests were mainly in semiconductor crystals and in certain oxide crystals but he also studied niobium with oxygen dissolved in it. The former had great practical importance in electronic devices and the latter were valuable in studying the phenomenon of ion channelling. He had shown that ionisation by a fast (MeV) light ion could damage the structure in silicon additional to the damage it did by creating collision cascades. He showed how to use channelling of MeV ions as an analytical tool to detect defects created by radiation damage or ion implantation, analyse their structure. Then he followed changes in their structure caused by heating and related the changes to bulk properties. These were important experiments as the technology of semiconductor devices was being developed and amongst his industrial collaborators were staff of the Phillips Laboratories at Redhill.  
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Derek Palmer’s interests were mainly in irradiation effects and defects in crystalline semiconductors, but he studied also irradiation-induced defects in the body-centred metals iron and niobium. The former had great practical importance for electronic devices and the latter provided valuable information relating to nuclear-reactor technology. He showed how to use channelling of MeV protons and helium ions, in association with Rutherford back scattering and proton-induced and 3He-induced nuclear reactions, as an analytical tool to detect defects created by radiation damage or ion implantation and to analyse their structures and properties.   A valuable fundamental feature, exploited in the work, of irradiation by light energetic ions is that the main ion-atom collision process is via nuclear-nuclear Coulomb interactions, and therefore that most of the collisions create lattice defects that are simple interstitials and vacancies.  Clear comparisons with electron-irradiation studies elsewhere could thence be made.  
  
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The phenomenon of channelling had been earlier studied by Derek Palmer in crystals of quartz. With a student he was in 1975 unravelling the fine detail of how channelled trajectories in another oxide crystal MgO change their direction from inter-axial to inter- planar. It is a process called scattering in the transverse plane, where this plane is perpendicular the crystal axis concerned, in which patterns emerge which can focus trajectories upon certain rows of atoms. This was being related by Derek Palmer’s student to the surface scattering experiments of Michael Thompson and his students. <br>(are we in touch with Derek and might he amend and perhaps add something?)
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An important innovation in the work by Derek Palmer was his setting up, on a beam line of the 2.0 MV Van de Graaff ion accelerator, of an experimental facility that allowed angle-resolved ion-channelling, in-situ irradiation and property measurement of semiconductor and metal samples at temperatures down to close to 4K.  That facility allowed irradiation-induced defects to be investigated before their thermally induced diffusion. Changes in the defect structures caused by heating were then studied in detail. For semiconductors, his investigations demonstrated that ionisation by fast (200 keV to 2.0 MeV) light ions could damage the lattice structure in silicon and germanium, additional to the disruption due to the nuclear-nuclear elastic collisions. Examples of particular results for metals (in work supported in part by AERE, UK) were the findings that the lattice sites of molybdenum atoms dissolved in iron and of oxygen atoms in niobium could be changed by their trapping of irradiation-induced point defects, and that that also allowed quantitative investigation of the thermally induced mobilities of the defects. 
  
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The phenomenon of channelling had been earlier studied by Derek Palmer in crystals of quartz. With a student he was in 1975 unravelling the fine detail of how channelled trajectories in another oxide crystal MgO change their direction from inter-axial to inter-planar. It is a process called scattering in the transverse plane, where this plane is perpendicular the crystal axis concerned, in which patterns emerge which can focus trajectories upon certain rows of atoms. This was being related by Derek Palmer’s student to the surface-scattering experiments of Michael Thompson and his students.
  
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Mike Lucas, before he joined the group had worked on the properties of defects in metals after irradiation with neutrons. His new interest was in the disturbance of the electrons in a solid by a very fast moving ion. He passed his ion beam through a thin solid and detected the electrons that emerged from the surface. These had their momentum analysed and it was found, surprisingly, that downstream of the foil, in the exact direction of the ion beam, the most probable speed of the electrons was the same as the speed of the ions. It was a result of great interest to theoreticians, several whom joined our group as collaborators and became frequent visitors. A new theory of the collision processes that excite electrons around a particle track was developed. The process responsible for the electrons emitted at the speed of the ions was called ‘charge capture to continuum states’. <br>(is Mike able to add something here?)
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It became clear, however, that the ion-channelling technique was not sensitive to the very low concentrations of lattice defects that could strongly affect the crucial electrical properties of semiconductors, and so Derek Palmer’s research moved into use of the DLTS (“Deep Level Transient Spectroscopy”) technique that investigates defects by their trapping and emission of electrons and holes in the semiconductors. Again the creation and properties of irradiation-induced defects at both cryogenic and higher temperatures needed to be investigated, and an in-situ DLTS cryostat was designed and was installed on a further ion-beam line of the Van de Graaff accelerator.  Because the use of proton-irradiation-induced defects to produce high resistivity regions in GaAs devices and integrated circuits was of much technological interest, Derek Palmer developed a close research link with the Philips Research Laboratory at Redhill, and he and his research students made detailed in-situ DLTS and associated electrical investigations on lattice defects in GaAs and on the related alloys Al(x)Ga(1-x)As and In(x)Ga(1-x)As. Indium phosphide was also of industrial interest, and DLTS investigations of light-ion created defects in that semiconductor were made in later work.   The work on GaAs etc and on InP produced valuable new results for irradiation-induced defects concerning their electronic energy levels, their thermal annealing properties and their natures.
  
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<br>Peter Townsend had a broader interest in ionisation by radiation. He studied insulating solids that were often crystalline, sometimes glassy and nearly always transparent. Optical properties and their relationship to crystal defects is a recurring theme in his publications (eg. Can one tailor optical properties?). He had just made a major contribution to theories of radiation damage by studying the creation of defects and sputtering of ions from ionic crystals like potassium iodide by irradiation with slow electrons. The electrons lacked the momentum to displace an atom by direct collision Even more surprising had been his prediction and demonstration that even ultraviolet light could sputter ions from the surface. The model correctly explained why the sputtering patterns of alkali and halogen ions were different. The theory of this process was a fascinating example of the radiation exciting an electron and this potential energy being transferred into kinetic energy on the nucleus of a single ion.  
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The experimental ion-irradiation / DLTS facility was subsequently supplemented by a rig that allowed in-situ uniaxial stress to be applied to semiconductor samples at temperatures down to about 10K before and after proton and helium ion irradiations.   The studies on n-type GaAs showed that uniaxial stress applied along the <100> and <110> crystallographic directions splits the electronic energy levels of each of the well known irradiation-induced defects E1, E2 and E3 into two levels of equal populations. Those experimental data showed that each of those lattice defects contains a single <111> crystallographic axis (ie, has C3v symmetry) and strongly suggested that E3 is an arsenic Frenkel defect, ie an arsenic interstitial-vacancy close pair, and that E1 and E2 may also be arsenic Frenkel pairs, but with different interstitial-vacancy separations. Those were the first ever uniaxial-stress studies on any irradiation-induced defect in GaAs.
  
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The phenomenon of thermo-luminescence was another of Peter Townsend’s interests especially when related to defects that could be introduced by radiation or by ion implantation. Crystals like lithium fluoride, which have important uses as radiation dosimeters in medicine and radiological protection, were being studied in 1975 and he built equipment to measure the emission spectra. This information was lacking from most other thermoluminescence research groups. As a consequence Sussex stayed in a lead position in this field for the next 30 years. In the late 1990’s this same type of equipment opened a novel route to detection of phase transitions, both of crystals and nanoparticle inclusions.
 
  
−
A third group of Peter Townsend’s experiments used high energy ions to damage the structure of glasses in a controlled layer beneath the surface. The depth of the layer was made comparable to the wavelength of light and he thus constructed optical waveguides. This work was to be of immense significance in developing the field of opto-electronics for smaller computers and optical fibres as transmission lines for telecommunication. It may be noted that Mike Thompson arranged a meeting with Charles Kao when he worked on this topic at the Standard Telecommunication and Cables Laboratories in the 1960s. At that point the potential of optical fibres had not been recognised by industry and the Sussex group were interested to see if ion implantation could be included in the processing. For the fibres this was not possible, but later, in 2009, Charles Kao received the Nobel Prize for Physics for making optical telecommunications possible. There was also some glory reflected on Sussex as this meeting prompted Peter Townsend to devise an ion implantation route to make optical waveguides in insulating crystals. This was a semi-universal route which has now been widely used in many more than 100 materials for waveguide lasers, non-linear optics and key items of modern photonics. Physics is a small community, as Townsend visited the Chinese University of Hong Kong in 1992 as the Wei Lun Professor whilst Professor Kao was Vice-Chancellor there.  
+
Mike Lucas, before he joined the group, had worked on the properties of defects in metals after irradiation with neutrons. His new interest was in the disturbance of the electrons in a solid by a very fast moving ion. He passed his ion beam through a thin solid and detected the electrons that emerged from the surface. These had their momentum analysed and it was found, surprisingly, that downstream of the foil, in the exact direction of the ion beam, the most probable speed of the electrons was the same as the speed of the ions. It was a result of great interest to theoreticians, several whom joined our group as collaborators and became frequent visitors. A new theory of the collision processes that excite electrons around a particle track was developed. The process responsible for the electrons emitted at the speed of the ions was called ‘charge capture to continuum states’.  
  
−
A collaborative project was set up with Professor Cahn’s Materials Sciences group in the School of Applied Sciences. Rob Wilshaw used ion implantation of H+ ions to assist the fracture of quartz crystals under mechanical stress. It was shown that even at low energies the implantation softened the quartz significantly. In application, it was hoped that the effect might reduce the energy expended in the crushing of minerals in the mining industry (RTZ). <br>
+
Peter Townsend had a broader interest in ionisation by radiation. He studied insulating solids that were often crystalline, sometimes glassy and nearly always transparent. Optical properties and their relationship to crystal defects is a recurring theme in his publications (e.g. Can one tailor optical properties?). He had just made a major contribution to theories of radiation damage by studying the creation of defects and sputtering of ions from ionic crystals like potassium iodide by irradiation with slow electrons. The electrons lacked the momentum to displace an atom by direct collision Even more surprising had been his prediction and demonstration that even ultraviolet light could sputter ions from the surface. The model correctly explained why the sputtering patterns of alkali and halogen ions were different. The theory of this process was a fascinating example of the radiation exciting an electron and this potential energy being transferred into kinetic energy on the nucleus of a single ion.  
  
−
== Postgraduate Teaching  ==
+
The phenomenon of thermo-luminescence was another of Peter Townsend’s interests, especially when related to defects that could be introduced by radiation or by ion implantation. Crystals like lithium fluoride, which have important uses as radiation dosimeters in medicine and radiological protection, were being studied in 1975 and he built equipment to measure the emission spectra. This information was lacking from most other thermoluminescence research groups. As a consequence, Sussex stayed in a lead position in this field for the next 30 years. In the late 1990’s this same type of equipment opened a novel route to detection of phase transitions, both of crystals and nanoparticle inclusions.
  
−
In this section the titles of the lecture courses open to the graduate students lays out the subject matter of our interests. A full list of all the staff serving in the group up to 1980 is given in Appendix A. A detailed picture of the research and its development over time can be gleaned from Appendix B which gives the names of all the graduate students, the titles of their theses and the names their supervisors. The onward careers of those early students is indicated rather briefly as for many of them details of their later lives are frequently unknown. However, over the subsequent years many of the Sussex graduates from the ion implantation group have made significant contributions to Physics and Materials Science. Of those who stayed in Academic environments there are numerous Professors, Head of Department, Deans and Vice Chancellors.  
+
A third group of Peter Townsend’s experiments used high energy ions to damage the structure of glasses in a controlled layer beneath the surface. The depth of the layer was made comparable to the wavelength of light and he thus constructed optical waveguides. This work was to be of immense significance in developing the field of opto-electronics for smaller computers and optical fibres as transmission lines for telecommunication. It may be noted that Mike Thompson arranged a meeting with Charles Kao when Kao worked on this topic at the Standard Telecommunication and Cables Laboratories in the 1960s. At that point the potential of optical fibres had not been recognised by industry and the Sussex group were interested to see if ion implantation could be included in the processing. For the fibres this was not possible, but later, in 2009, Charles Kao received the Nobel Prize for Physics for making optical telecommunications possible. There was also some glory reflected on Sussex as this meeting prompted Peter Townsend to devise an ion implantation route to make optical waveguides in insulating crystals. This was a semi-universal route which has now been widely used in many more than 100 materials for waveguide lasers, non-linear optics and key items of modern photonics. Physics is a small community, as Townsend visited the Chinese University of Hong Kong in 1992 as the Wei Lun Professor whilst Professor Kao was Vice-Chancellor there.
 +
 
 +
A collaborative project was set up with Professor Cahn’s Materials Sciences group in the School of Applied Sciences. Rob Wilshaw used ion implantation of H+ ions to assist the fracture of quartz crystals under mechanical stress. It was shown that even at low energies the implantation softened the quartz significantly. In application, it was hoped that the effect might reduce the energy expended in the crushing of minerals in the mining industry (RTZ).
 +
 
 +
 
 +
 
 +
== Postgraduate Teaching in the early years ==
 +
 
 +
In this section the titles of the lecture courses open to the graduate students lays out the subject matter of our interests. A full list of all the staff serving in the group up to 1980 is given in Appendix A. A detailed picture of the research and its development over time can be gleaned from Appendix B which gives the names of all the graduate students, the titles of their theses and the names their supervisors. The onward careers of those early students are indicated rather briefly, as for many of them, details of their later lives are frequently unknown. However, over the subsequent years many of the Sussex graduates from the ion implantation group have made significant contributions to Physics and Materials Science. Of those who stayed in Academic environments there are numerous Professors, Head of Department, Deans and Vice Chancellors.
  
 
The Physics Department taught all its research students in their first year enough additional physics to prepare them for their task. Short courses of lectures advanced their knowledge of quantum mechanics for example. More technical instruction was given to equip the students for using central computers, libraries and workshops. Where there were large enough groups to make it economical in staff time, specialised courses were given on that group’s subject, such as Condensed matter at low temperature, atomic and laser physics and particle-solid interactions.  
 
The Physics Department taught all its research students in their first year enough additional physics to prepare them for their task. Short courses of lectures advanced their knowledge of quantum mechanics for example. More technical instruction was given to equip the students for using central computers, libraries and workshops. Where there were large enough groups to make it economical in staff time, specialised courses were given on that group’s subject, such as Condensed matter at low temperature, atomic and laser physics and particle-solid interactions.  
  
−
In the latter our group developed an MSc course jointly with a group having similar interests at Salford University. It was entitled ‘Atomic Collisions in Solids’ and was described in its prospectus as follows:-  
+
In the latter our group developed an MSc course jointly with a group having similar interests at Salford University. It was entitled ‘Atomic Collisions in Solids’ and was described in its prospectus as follows:-
  
−
‘Atomic collisions in solids have attracted a great deal of attention in recent years. Processes such as atomic collision sequences and cascades, particle channelling, electron excitation and ion penetration are being studied in detail. The field has important applications in radiation damage, ion implantation, sputtering technology, electron microscopy, defect structures analysis and vacuum technology, many of which are basic to industrial processes. Modern advances have created a demand for education both from established scientists in Government and industrial laboratories and from new engineering and science graduates wishing to receive initial training. For the latter category over and above its intrinsic scientific value the subject involves a wide range of methods and techniques which make it an exceptionally valuable area for graduate training.’………….  
+
‘Atomic collisions in solids have attracted a great deal of attention in recent years. Processes such as atomic collision sequences and cascades, particle channelling, electron excitation and ion penetration are being studied in detail. The field has important applications in radiation damage, ion implantation, sputtering technology, electron microscopy, defect structures analysis and vacuum technology, many of which are basic to industrial processes. Modern advances have created a demand for education both from established scientists in Government and industrial laboratories and from new engineering and science graduates wishing to receive initial training. For the latter category over and above its intrinsic scientific value the subject involves a wide range of methods and techniques which make it an exceptionally valuable area for graduate training.’………….
  
−
…‘we offer a course beginning in October 1971, built upon a set of seven modules lasting about three weeks each. All of these could be taken individually by short term students whilst an approved selection of four, together with a project, will make a student eligible for an MSc award’…..  
+
…‘we offer a course beginning in October 1971, built upon a set of seven modules lasting about three weeks each. All of these could be taken individually by short term students whilst an approved selection of four, together with a project, will make a student eligible for an MSc award’…..
  
−
…..’while the majority of the tuition will be given by University staff we recognise that great expertise in this field resides in government and industrial research laboratories. We are therefore making extensive use of visiting professors from Harwell and invited speakers from industry.  
+
…..’while the majority of the tuition will be given by University staff we recognise that great expertise in this field resides in government and industrial research laboratories. We are therefore making extensive use of visiting professors from Harwell and invited speakers from industry.
  
−
In addition, the universities may permit an MSc student, in approved circumstances, to satisfy the project requirement by work carried out in an external organisation.’….  
+
In addition, the universities may permit an MSc student, in approved circumstances, to satisfy the project requirement by work carried out in an external organisation.’….
  
−
The titles of the modules were:-  
+
The titles of the modules were:-
  
−
#''Theory of the defect solid state and atomic collision processes''
+
‘1 Theory of the defect solid state and atomic collision processes
−
#''Radiation damage''
+
2 Radiation damage
−
#''Structural analysis of crystals''
+
3 Structural analysis of crystals
−
#''Ion implantation''
+
4Ion implantation
−
#''Ion beam technology''
+
5 Ion beam technology
−
#''Composition analysis of solids''
+
6 Composition analysis of solids
−
#''High vacuum and high voltage technology''
+
7 High vacuum and high voltage technology’
  
−
The course ran from 1971 to 1974. 33 MSc awards were made by Sussex University and a similar number by Salford. The Science Research Council provided some funding for approved students and this style of graduate course became a model that other universities followed. <br> <br>Our DPhil students, as part of their initial course work, went through such modules as were appropriate to their research topic and some of the MSc students were offered the chance of continuing for the DPhil qualification. Even after the MSc course closed several of the modules continued for the DPhil coursework.  
+
The course ran from 1971 to 1974. 33 MSc awards were made by Sussex University and a similar number by Salford. The Science Research Council provided some funding for approved students and this style of graduate course became a model that other universities followed.
 +
 +
Our DPhil students, as part of their initial course work, went through such modules as were appropriate to their research topic and some of the MSc students were offered the chance of continuing for the DPhil qualification. Even after the MSc course closed several of the modules continued for the DPhil coursework.  
  
−
In appendix A we list all the Sussex staff members by category, academic, postdoctoral, technical and clerical; also the Salford academic staff, the visiting professors and the industrial collaborators who assisted in the supervision of Sussex students.  
+
In appendix A we list all the Sussex staff members by category, academic, postdoctoral, technical and clerical; also the Salford academic staff, the visiting professors and the industrial collaborators who assisted in the supervision of Sussex students. This list includes those who were associated with the early course, and does not attempt to list the very many, and distinguished visitors who came to the group in later years.
  
−
In appendix B we list all of the Sussex graduate students with their years, the name of their supervisor and the title of their dissertation or thesis. It may also be of interest to note the subsequent employment of our students after graduating and where we have the information this is included.<br>
+
In appendix B we list the Sussex graduate students with their years, the name of their supervisor and the title of their dissertation or thesis. This list is not confined to the initial years, but attempts to include everyone up to the 2010 when the accelerator group was finally closed. A summary of the initial employment from the early students and the current (2010) employment is noted where possible. We regret that the 2010 list is far from complete although many distinguished people are cited.
  
−
== Conclusion  ==
+
 
 +
== Overview of the initial Ion Implantation group at the time of Professor Thompson ==
  
 
How well did the Particle-Solid Interactions Group perform the mission it began in 1965? Certainly it played its part in proving that the new University of Sussex would be able to support research at an internationally recognised level and to win research grants in competition with long-established universities. In 1961 in some influential circles this had been doubted. This account gives a snapshot of the work in progress in one research group in the mid to late 1970s. But it was but one of many groups of equal distinction flourishing in Sussex in that period.  
 
How well did the Particle-Solid Interactions Group perform the mission it began in 1965? Certainly it played its part in proving that the new University of Sussex would be able to support research at an internationally recognised level and to win research grants in competition with long-established universities. In 1961 in some influential circles this had been doubted. This account gives a snapshot of the work in progress in one research group in the mid to late 1970s. But it was but one of many groups of equal distinction flourishing in Sussex in that period.  
  
−
It must not be thought from reading this history that the five academic staff devoted all their energies to research and postgraduate teaching. Each of them carried a full share of university duties that included undergraduate teaching, examining and administration. The proportion of each activity was different for each of them. Was the content of their undergraduate courses changed by this research? Rather little one suspects, because the research results were usually too detailed to include in the wider curriculum. But the quality of their teaching and its effect upon their students probably was enhanced. Amongst the many reasons are first, the depth of reading that one does to support personal research deepens ones understanding of Physics in concept and in technique and that makes one a better teacher of the general subject. Second, the experiences of research sharpen one’s mind to make it more critical of information received, whether from one’s own experiment or the account of someone else’s. When that critical approach is transferred through teaching Experimental Physics to undergraduates they will learn how to judge information for themselves, not only becoming better physicists but also better citizens.  
+
It must not be thought from reading this history that the five academic staff devoted all their energies to research and postgraduate teaching. Each of them carried a full share of university duties that included undergraduate teaching, examining and administration. The proportion of each activity was different for each of them. Was the content of their undergraduate courses changed by this research? Rather little one suspects, because the research results were usually too detailed to include in the wider curriculum. But the quality of their teaching and its effect upon their students probably was enhanced. Amongst the many reasons are first, the depth of reading that one does to support personal research deepens ones understanding of Physics in concept and in technique and that makes one a better teacher of the general subject. Second, the experiences of research sharpen one’s mind to make it more critical of information received, whether from one’s own experiment or the account of someone else’s. When that critical approach is transferred through teaching Experimental Physics to undergraduates they will learn how to judge information for themselves, not only becoming better physicists but also better citizens.
  
−
In the early formative years of the group at least 50 graduate students were awarded higher degrees as a result of work they did in this group. In direct ways they were taught how to do research and they were given substantial knowledge. But they also learned for themselves and in graduating proved that they knew how to explore further and to make their own maps of knowledge. From the careers that can be tracked it seems likely that the individuals’ prospects were enhanced by the time the spent here and the people the met. That should be the proper outcome to education at any level. But in addition one might note the evident utility of the research and the outcomes for the benefit of institutions both public and private and the lives of people in general.  
+
In the early formative years of the group at least 50 graduate students were awarded higher degrees as a result of work they did in this group. In direct ways they were taught how to do research and they were given substantial knowledge. But they also learned for themselves and in graduating proved that they knew how to explore further and to make their own maps of knowledge. From the careers that can be tracked it seems likely that the individuals’ prospects were enhanced by the time the spent here and the people the met. That should be the proper outcome to education at any level. But in addition one might note the evident utility of the research and the outcomes for the benefit of institutions both public and private and the lives of people in general.
  
−
== Postscript  ==
+
== The group and its development in later years ==
  
−
Undoubtedly the driving force of the initial implantation group was Professor Mike Thompson. Consequently the emphasis on the various topics changed somewhat when he moved into administrative posts at Sussex, and then left to become a Vice Chancellor of East Anglia ( dates) and then on to Birmingham (…). His skill in these new tasks was recognised by a knighthood in&nbsp;????. Ion implantation however remained a key experimental focus for Drs Lucas, Palmer and Townsend and all three had a significant scientific output from the accelerator laboratory.<br>The group of Professor Townsend built on their earlier techniques of optical effects of ion implantation and these were complemented by his laser, luminescence and thermoluminescence activities. There was considerable funding both from UK Research Councils, foreign industry and many European research programmes. Hence there were many effective collaborations and research visitors and students to the laboratory until its closure in 2010. A particularly key figure in the later years was Dr David Hole, who not only ran the 3MV machine, in close association with the experiments of Peter Townsend, but also had his own major programme with the JET laboratory on analysis of materials used in the development of Tokamaks. So, atomic energy was both at the beginning and at the end of the accelerator group’s research programme.<br>Monitors of success from the Townsend group included some 44 DPhil students and more than 20 MPhil and MSc degrees. Townsend was named the lead candidate for the Engineering section of the 2004 Descartes Prize on Excellence in Research for his work on improving photomultiplier tubes and their application for Optical Biopsy in breast cancer detection. In 2008 there was also a small celebration to note Townsend’s 500th publication. Subsequent Sussex publications from both Townsend and Hole are still emerging.  
+
Undoubtedly the driving force of the initial implantation group was Professor Mike Thompson. Consequently the emphasis on the various topics changed somewhat when he moved into administrative posts at Sussex, and then left to become a Vice Chancellor of East Anglia and then on to Birmingham. His skill in these new tasks was recognised by a knighthood. Ion implantation however remained a key experimental focus for Drs Lucas, Palmer and Townsend and all three had a significant scientific output from the accelerator laboratory as well as their work in related areas of solid state and materials science.
  
−
<br>
+
The group of Professor Townsend built on their earlier techniques of optical effects of ion implantation and these were complemented by his laser, luminescence and thermoluminescence activities. There was considerable funding both from UK Research Councils, foreign industry and many European research programmes. Hence there were many effective collaborations and research visitors and students to the laboratory until its closure in 2010. A particularly key figure in the later years was Dr David Hole, who not only ran the 3MV machine, in close association with the experiments of Peter Townsend, but also had his own major programme with the JET laboratory on analysis of materials used in the development of Tokamaks. So, atomic energy was both at the beginning and at the end of the accelerator group’s research programme.
  
−
Should there be more in this section from Mike Lucas and Derek Palmer?
+
Monitors of success from the Townsend group included some 47 DPhil students and more than 20 MPhil and MSc degrees. Townsend was named the lead candidate for the Engineering section of the 2004 Descartes Prize on Excellence in Research for his work on improving photomultiplier tubes and their application for Optical Biopsy in breast cancer detection. In 2008 there was also a small celebration to note Townsend’s 500th publication. Subsequent Sussex publications from both Townsend and Hole are still emerging.
 +
 
 +
MWL, DWP, MWT and PDT January 2011
  
−
<br>MWT+ PDT<br>
 
  
−
<br>
 
  
 
== APPENDIX A  ==
 
== APPENDIX A  ==
  
−
Staff (we probably need some more in and out dates for the Sussex team)
+
Key members of the ion implantation group joint programme
  
−
University of Sussex University of Salford (collaboration 1971-75)  
+
Staff 
 +
University of Sussex                                                                                                         University of Salford (collaboration 1971-75)
  
−
Professor M W Thompson, Prof. of Experimental Physics, (1965-80) Professor G Carter, Prof. of Physical Electronics<br>Dr M W Lucas, Lecturer in Physics (1966--- )&nbsp;? D G Armour, Lecturer in Electrical Engineering<br>Dr D W Palmer ,, (1966- --)&nbsp;? Dr J S Colligon ,,<br>Dr P D Townsend ,, (1966---)&nbsp;? Dr W A Grant ,,<br>Dr J A Venables ,, (1963- )&nbsp;? Dr F Paton ,,<br>Professor R W Cahn, Prof of Materials Science (1963-80) Dr R Andrews ,,<br> Dr G Farrell ,,<br>Professor G Dearnaley, Visiting Professor, AERE Harwell Dr G A Stephens ,,<br>Professor R S Nelson ,, ,, <br>Dr B L Eyre, External supervisor, AERE Harwell <br>Dr A E Hughes, ,, ,,<br>Dr M J Makin, ,, ,, <br>Dr P Blood ,, Phillips Research Labs.<br>Dr J Shannon ,, ,,<br>(a few more here I think)
+
Professor M W Thompson, Prof. of Experimental Physics, (1965-80)                       Professor G Carter, Prof. of Physical Electronics
 +
Dr M W Lucas, Lecturer in Physics                                     (1966-93)                           D G Armour, Lecturer in Electrical Engineering
 +
Dr D W Palmer   Lecturer/Senior Lecturer                          (1966-98)                           Dr J S Colligon                   ,,
 +
Dr P D Townsend   Lecturer/Reader/Professor                    (1966-2009)                       Dr W A Grant                     ,,
 +
Dr J A Venables           ,,                                                       (1963- )                             Dr F Paton                         ,,
 +
Professor R W Cahn, Prof of Materials Science                   (1963-80)                           Dr R Andrews                   ,,
 +
                                                                                                                                          Dr G Farrell                       ,,
 +
    Dr G A Stephens               ,,
  
−
R A R Bayly, Research Fellow in Physics (1970-73)&nbsp;?<br>Dr P Combasson ,, (1976)<br> Dr K H Ecker ,, (1971-73)<br>Dr L Holland ,, (1974-75)<br>Prof J C Kelly (senior visiting) ,, (1967 &amp; 1974) <br>Dr J O’Connor ,, (1979-81) <br>Dr H J Pabst ,, (1973-76)<br>Dr A P Pathak ,,<br>Dr M Saidoh ,, (1975-76)<br>Dr D van Vliet ,, (1967-70)<br>Dr W Steckelmacher ,, (1974- )&nbsp;?<br>Dr T R Wilshaw, Research Fellow in Materials Science ( 1968-71)<br>Dr I H Wilson, Research Fellow in Physics (1965-68)<br>(and here)
+
Associated visitors in the first few formative years of the group included
 +
Professor G Dearnaley, Visiting Professor, AERE Harwell                                             
 +
Professor R S Nelson                        ,,               ,,                                                            
 +
Dr B L Eyre, External supervisor, AERE Harwell                                                           
 +
Dr A E Hughes,               ,,                     ,,
 +
Dr M J Makin,               ,,                     ,,  
 +
Dr P Blood                    ,,             Philips Research Labs.
 +
Dr J Shannon                  ,,                         ,,
  
−
Mr B W Farmery, Experimental Officer in Physics<br>Mr E Turpin, Technician <br>Mr N Priestley ,,<br>Mr D Hole ,, <br>Mr A Houghton ,,<br>Miss J Teare ,,  
+
The Research Fellows / Research Assistants (“RF/A”), local & visiting collaborators included the following:
 +
Dr S Alaya                                                          (1994, 1996, 1997)
 +
Dr R A R Bayly,      RF/A, Physics                  (1970-73)
 +
Dr M Ben-Salem                                                (1995, 1996)
 +
Dr P Combasson, RF/A, Physics                        (1976)
 +
Dr C Comrie                                                        (1979-80)
 +
Dr J O’Connor    RF/A, Physics                        (1979-81)
 +
Dr M Domkus                                                    (1982-83)
 +
V A Dravin                                                          (1997, 1998)
 +
Dr K H Ecker        RF/A, Physics                     (1971-73)
 +
Prof. P C Euthymiou                                          (1992)
 +
Dr G E Giakoumakis                                      (1985, 1992)
 +
Prof. A A Gippius                                          (1992)
 +
Dr A H M Husain                                            (1983-84)
 +
Dr L Holland                                                  (1974-75)
 +
Prof J C Kelly                                                  (1967 & 1974)
 +
Dr A H M Husain                                            (1983-84)
 +
Dr R E Kaim                                                  (1979)
 +
Prof. H Maaref                                                (1993, 1995, 1997)
 +
Dr H J Pabst    RF/A, Physics                        (1973-76)
 +
Dr A P Pathak                   
 +
Dr A A Rezazadeh                                        (1982-84)                 
 +
Dr M Saidoh                                                  (1975-76)
 +
Dr A  V Spitsyn                                              (1981)
 +
Dr M A Subhan                                              (1981)
 +
Dr T Taguchi                                                  (1979-80)
 +
Dr D Titley        RF/A, Physics                       
 +
Dr V V Ushakov                                              (1994)                                 
 +
Dr D van Vliet    RF/A, Physics                      (1967-70)
 +
Dr W Steckelmacher, RF/A, Physics              (1974-  )
 +
Dr T R Wilshaw, RF, Materials Science      (1968-71)
 +
Dr I H Wilson,     RF, Physics                      (1965-68)   
 +
Dr G Zardas                                                  (1987)
  
−
Miss N Kingan Secretary (1965-69)<br>Mrs M Tait ,, (1969 – 8?)  
+
Mr B W Farmery, Experimental Officer in Physics
 +
Mr E Turpin, Technician
 +
Mr N Priestley      ,,
 +
Mr D Hole            ,, 
 +
Mr A Houghton    ,,
 +
Miss J Teare          ,,
 +
Miss N Kingan     Secretary (1965-69)
 +
Mrs M Tait                 ,,       (1969 – )    
 +
                                                                                                                               
 +
A working pattern of having visitors, both senior and postgraduate student level became firmly established and Sussex has benefitted considerably from this strategy. Many senior people have visited with funding from SERC, EPSRC, The Royal Society, EC funding, or other travel grants. Additionally the links have involved visiting students to Sussex, both at the graduate and undergraduate level. A complete chronological list of such visits is difficult to reconstruct as it involves several hundred people, many of whom have visited on many occasions. The following list therefore is intended to be indicative of the pattern and only cites a very few of the more long term collaborations. From the viewpoint of publications the same visitors are frequently co-authors together with members of their own research groups. This global pattern of research is highlighted by a brief head count of co-authors, and their countries, of Peter Townsend. In about 2008 he passed the 500 publication mark and at that stage had some 450 co-authors from 42 different countries.
 +
 
 +
Mike Lucas had a long term collaboration with
 +
Prof K Dettmann at University of Freiburg-im-Breisgau
 +
Prof J Macek at University of Nebraska
 +
Prof K O Groeneveld at J W Goethe University, Frankfurt
 +
Dr. D H Jakubassa-Amundsen at University of Munich
 +
 
 +
Derek Palmer had long term collaborations with
 +
          Professor P C Euthymiou, University of Athens, Greece
 +
Dr G E Giakoumakis, University of Ioannina, Greece
 +
          Professor A A Gippius, P N Lebedev Physical Research Institute, Moscow
 +
Professor H Maaref, Université du Sud, Monastir, Tunisia
 +
 
 +
Barry Farmery started a research programme with Dr Paul Coad at the JET lab in Culham. This was then expanded by Dr David Hole until the accelerator closure in 2010. The research has been key to assessing the problems of materials damage and transport within the Tokomak fusion reactor vessel in JET. The programme and our equipment has now moved to Portugal to continue work for ITER.
 +
 
 +
Peter Townsend had a very fruitful collaboration with Southampton and University College London with work on laser waveguides and photonics; a collaboration since 1974 with many member of the Universidad Autonoma de Madrid which generated some 50 publications, for which he received a Doctor Honoris Causa; Visits from Professor Bairui Yang and her students from Beijing have been particularly effective in terms of thermoluminescence publications and development of a new field of optical detection of phase transitions; a 6 year collaboration with Societa Italiana Vetro provided considerable accelerator funding, many papers and patents, and detailed studies of optical effects of ion implantation in glass. A number of EC funded programmes have advanced Condensed matter work from Sussex, and in particular, spectacular advances in the performance of photomultiplier tubes. In their use for breast cancer detection this resulted in the group leading the 2004 Engineering section of the prestigious Descartes prize. There was also a long term collaboration (~35 papers) with Prof Helen Rendell combining luminescence measurements with geological and thermoluminescence dating and analysis. This interest expanded to include several other partners from Madrid and St Andrews.
  
 
== <br>APPENDIX B  ==
 
== <br>APPENDIX B  ==
 +
A chronological list of postgraduate students from the research group from 1966 to 2010
 +
 +
 +
Name                                Degree            Dates                    Supervisor                                Title of Thesis
 +
 +
A D Marwick                    DPhil            1966-70                  M W Thompson        Channelling and Surface Scattering
 +
 +
 +
C Foster                              DPhil            1966-70                I H Wilson                  Atomic Scattering and Interatomic Potentials                 
 +
                                                                                              M W Thompson
 +
                                                                                                         
 +
 +
Z Sumengen                        MSc            1966-67                D W Palmer                Channel Electron Multipliers as Detectors of 
 +
                                                                                                                                      Electrons and Protons
 +
 +
G Chapman                        DPhil            1967-71                M W Thompson        High Energy Sputtering
 +
 +
 +
B Stocking                          MSc            1967-8                  M W Lucas                Measurement of the Surface Density of Thin 
 +
                                                                                                                                      Foils                         
 +
                                                                                                                       
 +
J D Haskell                        MSc            1967-8                    D W Palmer
 +
 
 +
M Kidd                              MSc            1967-8                    P D Townsend            Topography of Sputtered Surfaces
 +
 +
D Richards                        MSc            1968-69                  P D Townsend          Sputtering Measurements of Silica and Sodium   
 +
                                                                                                                                        chloride
 +
 +
T G Williams                      DPhil          1968-71                  D W Palmer                Ion Channelling and Irradiation Effects in 
 +
                                                                                                                                        Gallium Arsenide
 +
 +
D J Elliot                            DPhil          1968-71                  P D Townsend          Low Energy Ion Irradiation in Alkali Halide 
 +
                                                                                                                                        Crystals
 +
 +
N E W Hartley                  DPhil          1968-71                  R W Cahn                  The Comminution of Minerals, some Fracture and
 +
                                                                                              T R Wilshaw                Deformation Studies on Quartz with  reference to 
 +
                                                                                                                                    Size Reduction                                                                                                         
 +
 +
G S Harbinson                    DPhil          1969-73                  M W Thompson        X-Ray Production and Ion Scattering from
 +
                                                                                                                                      Surfaces
 +
 +
P J Mac Donald                  DPhil          1969-73                  D W Palmer                Ion Implantation in Germanium
 +
 +
G C Crittenden                  DPhil          1969- 73                P D Townsend          Thermoluminescence in Doped LiF 
 +
 +
R Browning                        MSc            1969-70                  P D Townsend          Defect Formation in Alkali Halides         
 +
     
 +
                                          DPhil            1971-74                            ,,                      Sputtering Patterns from Electron Irradiated   
 +
                                                                                                                                      Alkali Halides
 +
 +
K G Harrison                    DPhil          1969-71                  M W Lucas                Beam Foil Electron Spectroscopy
 +
 +
H J Pabst                            DPhil          1969-73                  D W Palmer                A Channelling Study of Defects in Silicon
 +
 +
A H G El Dhaher              MSc            1969-70                  D W Palmer                A 60 kV Accelerator System for Low Energy
 +
                                                                                                                                      Channelling Studies
 +
 +
N M Khan                          DPhil          1970-74                  M W Lucas                Charge Exchange to the Continuum in Single 
 +
                                                                                                                                      Crystals
 +
 +
T C Ang                            MSc            1970-71                  P D Townsend          Colour Centres in Silica induced by Ion
 +
                                                                                                A R Bayley                    Implantation
 +
 +
        Y Al Jammal                      MSc            1971-72                  P D Townsend          Electron Produced Sputtering of Alkali  halides
 +
                                                                                                       
 +
          T F Bartley                        MSc            1971-72                  M W Lucas                Measurement of Equilibrium Charge-Fraction  ratios
 +
                                                                                                                                      of H+ , H2+ and H3+ Ions in Carbon using
 +
                                                                                                                                      Continuous Channel Electron multipliers
 +
                                                                                                                                                 
 +
D Bean                              MSc            1971-72                  L Holland                  The Cleaning of Silicate Glass Surfaces in a     
 +
                                                                                                                                      Radiofrequency Discharge
 +
 +
J P Davies                          MSc            1971-2                    D W Palmer              An Investigation of the Channelography  technique
 +
 +
G G W Durbin                  MSc            1971-72                  J A Venables            Low Temperature Observations of Li and Na  in the
 +
                                                                                                                                        Scanning Electron Microscope
 +
 +
J M Gilkes                          MSc            1971-72                  P D Townsend            Spectral Investigation of the Thermoluminescent
 +
                                                                                                                                        process in LiF
 +
 +
G W Nielsen                      MSc            1971-72                  M W Thompson        Rutherford Scattering from Metals
 +
                                           
 +
                                          DPhil          1972-76                          ,,                        A Rutherford Backscattering Study of Heavy  ion
 +
                                                                                                                                        Ranges in Polycrystalline Aluminium and 
 +
                                                                                                                                        Amorphous Silicon
 +
 +
R R Arstrong                    MSc            1972-73                  D W Palmer                Channelography of Thin Metal Foils
 +
 +
P Barw                              MSc            1972-73                  M J Makin                Irradiation Damage Studied by High Voltage
 +
 +
                                          DPhil          1973-75                  J A Venables              Electron Microscopy                                                       
 +
 +
P J Chandler                      MSc            1972-73                    R S Nelson                Surface Studies Using Ion Bombardment
 +
                                                                                                P D Townsend
 +
 +
          J D Lee                              MSc            1972-73                    A E Hughes              Radiation Damage in Electrical and Optical
 +
                                                                                                P D Townsend              Components
 +
 +
B T Meggitt                      MSc            1972-73                    M W Lucas                Charge States of Hydrogen Atoms Traversing Foils
 +
                                                                                                                                                   
 +
I I Sheikh                            MSc            1972-73                  P D Townsend          Thermoluminescence Defect Studies in Lithium
 +
                                                                                                                                        Fluoride
 +
 +
J P Sum  rs                        MSc            1972-73                  B L Eyre                    Electron Microscope Studies of Self-Ion  Damage
 +
                                                                                                J A Venables                  in Copper
 +
 +
R E J Watkins                    MSc            1972-73                    G Dearnaley              Radiation Enhanced Diffusion in Metals             
 +
                                                                                                M W Thompson
 +
 +
P Barker                            MSc            1973-74                  D W Palmer              Proton Irradiation of Germanium
 +
 +
S Datta                              MSc            1973-74                  A E Hughes                Luminescence Dosimetry using LiF
 +
                                                                                                P D Townsend
 +
 +
S E Donelly                        MSc            1973-74                  R S Nelson                Diffusion of Inert gases in Metals
 +
 +
 +
D W Garlant                      MSc            1973-74                  P D Townsend          Luminescence during the Sputtering of Alkali
 +
                                                                                                                                        Halides
 +
 +
J W Muncie                        MSc            1973-74                  B L Eyre                    Proton Damage in Metals Studied by Electron 
 +
                                                                                                J A Venables                  Microscopy
 +
 +
R Bin Jaya                          MSc            1974-75                  J A Venables            Use of the Scanning Microscope to Obtain
 +
                                                                                                                                        Crystallographic Information
 +
 +
M Brown                            MSc            194-75                    D  W Palmer              Computer Simulation Calculation of Proton
 +
                                                                                                H J Pabst                        Damage in Silicon
 +
 +
A Mahjoubi                        MSc            1974-75                  P D Townsend            Sputtering of Alkali Halides
 +
 +
A Nyaiesh                          MSc            1974-75                  M W Lucas                Stopping Power for Protons and Molecular 
 +
                                                                                                                                        Hydrogen Ions
 +
 +
P Goode                              MSc (p/t)    1972-75                  G Dearnaley                Study of the Effects of Ion Implantation on 
 +
                                                                                                                                          the Thermal Oxidation of Nickel 
 +
 +
R W Cranage                      DPhil          1972-75                  M W Lucas                Absolute Cross sections for Charge Exchange to
 +
                                                                                                                                          the Continuum
 +
 +
I Reid                                  DPhil          1971-76                  M W Thompson        Sputtering Processes in Gold
 +
 +
S D Mukherjee                  DPhil          1973-76                  D W Palmer                A Study of Proton Channelling and
 +
                                                                                                                                        Dechanneling in MgO
 +
 +
A P Webb                          DPhil          1973-76                  P D Townsend            Refractive Index Changes Produced in Silica by
 +
                                                                                                                                          Ion Implantation
 +
 +
 +
B Cefalas                            MSc            1976-77                  P D Townsend          Temperature Effect on Refractive Index Changes
 +
                                                                                                                                        Formed by Ion Implantation
 +
 +
M Wintersgill                    DPhil          1974-77                  P D Townsend          Luminescence in LiF: Mg: Ti
 +
 +
R Strong                              DPhil          1974-77                  M W Lucas                Electron Loss From Light Ions
 +
 +
R E Kaim                            DPhil          !974-77                  D W Palmer              Oxygen Locations and Oxygen-Defect
 +
                                                                                                                                        Interactions in Ion Irradiated Niobium
 +
 +
P J Chandler                      DPhil          1974-77                  P D Townsend          Radiation Induced Fluorescence in Insulators
 +
 +
        P Barker                              DPhil          1975-78                  D W Palmer                A Study of Proton- Irradiation Damage of
 +
                                                                                                                                                  Germanium
 +
 +
S Ahmad                            DPhil          1976-80                  M W Thompson        Effect of Ion Mass on the Energy Spectra of
 +
                                                                                                                                        Sputtered Gold Atoms
 +
 +
H J Whitlow                      DPhil          1977-80                  M W Thompson        Low Energy Ion Implantation of Silicon
 +
                                                                                                        D J O’Connor
 +
       
 +
C D Meekison                    DPhil          1978-81                  D W Palmer              rradiation Effects in Degassed and
 +
                                                                                                                                                  Oxygen-Doped Niobium
 +
 +
        A A Rezazadeh                  DPhil          1979-82                  D W Palmer                Electrical Studies of Gallium Arsenide         
 +
                                                                                                                                                  Irradiated by Light Ions and Electrons
 +
 +
PW Haycock     MSc 1980-81         P D Townsend          Polarisation studies in lithium niobate and
 +
                                    lithium tantalate
 +
         
 +
M Kijek                              DPhil          1980-83                  D W Palmer                Application of Nuclear Reaction and RBS 
 +
                                                                                                                                      Techniques for Studies of Impurity Diffusion in
 +
                                                                                                                                      Metallic Glasses
 +
 +
KI Ahmed                 MPhil 1981-83         P D Townsend            Emission spectra during thermoluminescence
 +
 +
DEM Arafah                 DPhil 1981-84         P D Townsend          Defect studies in insulators using ion beam techniques
 +
         
 +
        KF Man     DPhil          1981-84                  M W Lucas         Electron loss to the continuum
 +
 +
AB Faik     DPhil 1981-84         P D Townsend          Refractive index measurements of ion exchanged
 +
and ion implanted waveguides
 +
 +
D Georgiacodis                  DPhil          1981-84                  D W Palmer         Low Temperature Ion-Irradiation Effects in Silicon           
 +
                                                                                                                                        Studied by the Ion-Channelling Technique
 +
                                                                                                                                                 
 +
P S Nandhra                      DPhil          1982-85                  D W Palmer              Electrical Characterisation of High-Dose
 +
                                                                                                                                        Proton-Irradiated MBE Gallium Arsenide
 +
 +
N S McCartney                  D Phil          1983-86                  D W Palmer              Helium-Ion Irradiation Effects in Ferritic Iron Alloys
 +
                                                                                                                                         
 +
WO Siyanbola     MSc 1985-86         P D Townsend          Thermoluminescence of zircons
 +
 +
JA Strain     DPhil 1984-86         P D Townsend          Angular distributions of sputtered particles
 +
 +
PW Haycock     DPhil 1984-86         P D Townsend          Ion beam induced luminescence and
 +
polarisation reversal in ferroelectric crystals
 +
 +
Hanafi Atan                        MSc            1984-86                  M W Lucas                Collision Induced Autoionisation of 2.0 - 2.4 MeV
 +
                                                                                                                                      Ar+ and O+ Ions
 +
 +
F Lama       DPhil 1984-86         P D Townsend          Sputtering processes in UO2 and UF4
  
−
''Postgraduate Students''
 
  
−
''Name Degree Dates Supervisor Title of Thesis''
+
C P Hobbs                          DPhil          1985-88                  D W Palmer                The Effects of Surface Topography and of  Sample
 +
                                                                                                                                        Heterogeneity in Nuclear Microprobe 
 +
                                                                                                                                        Ion-Beam Analysis
  
−
A D Marwick DPhil 1966-70 M W Thompson Channelling and Surface Scattering
+
SE Lax     DPhil 1985-87         P D Townsend          Refractive index profiles produced by ion
 +
implantation in insulators
  
−
<br>C Foster DPhil 1966-70 I H Wilson Atomic Scattering and Interatomic Potentials <br> M W Thompson<br>
+
LH Abu-Hassan     DPhil 1985-87         P D Townsend          Optical studies of ion beam irradiated LiF and SiO2
  
−
Z Sumengen MSc 1966-67 D W Palmer Channel Electron Multipliers as Detectors of Electrons and Protons
+
Hanafi Atan                        DPhil          1986-89                  M W Lucas                Charge Changing and Multipole Expansions of
 +
Electron Loss to the Continuum
  
−
G Chapman DPhil 1967-71 M W Thompson High Energy Sputtering
+
        W O Siyanbola                    DPhil         1986-89                  D W Palmer              Production and Annealing of Proton-
 +
                                                                                                                                                Irradiation-Induced Defects in n-GaAs
  
−
<br>B Stocking MSc 1967-8 M W Lucas Measurement of the Surface Density of Thin Foils
+
EK Glavas     DPhil 1986-88         P D Townsend          Ion implanted optical waveguides in lithium
 +
tantalate and lithium niobate
  
−
M Kidd MSc 1967-8 M W Thompson Topography of Sputtered Surfaces
+
        DA Parks                            DPhil          1986-89                  P D Townsend          TL dating and geochemistry of brickearths in SE
 +
  England
  
−
<br>D Richards MSc 1968-69 P D Townsend Sputtering Measurements of Silica and Sodium Chloride
+
BJ Luff     DPhil 1986-89         P D Townsend           Cathodoluminescence of oxides
  
−
<br>T G Williams DPhil 1968-71 D W Palmer Ion Channelling and Irradiation Effects in Gallium Arsenide
+
AAS Al-GHamdi              DPhil           1986-89               P D Townsend          Optical studies associated with ion irradiated
 +
oxide materials
  
−
D J Elliot DPhil 1968-71 P D Townsend Low Energy Ion Irradiation in Alkali Halide Crystals
+
RA Wood     DPhil 1987-90         P D Townsend           Optical absorption studies in Al2O3 LiNbO3
 +
and LiF during ion implantation
  
−
N E W Hartley DPhil 1968-71 R W Cahn &amp; T R Wilshaw The Comminution of Minerals, some Fracture and Deformation Studies on Quartz with reference to Size Reduction
+
P Abrahams                        MSc            1987-88                  D W Palmer 
  
−
G S Harbinson DPhil 1969-73 M W Thompson X-Ray Production and Ion Scattering from Surfaces
+
ND Skelland     MSc 1989-90         P D Townsend          Silver colloids in glass
 +
L Zhang     DPhil           1987-90         P D Townsend          Ion implanted waveguides in electro-optic and
 +
laser materials
  
−
P J Mac Donald DPhil 1969-73 D W Palmer Ion Implantation in Germanium
+
CA Perks     DPhil 1988-91         P D Townsend            Techniques for TL glow curve analysis and
 +
dose response of individual glow peaks in LiF
  
−
<br>G C Crittenden DPhil 1969- 73 P D Townsend Thermoluminescence in Doped LiF
+
AC Irvine                            DPhil         1989-92                  D W Palmer                Lattice Defects in As-Grown and Irradiated
 +
                                                                                                                                        GaAs, AlGaAs and InGaAs 
  
−
<br>R Browning MSc 1969-70 P D Townsend Defect Formation in Alkali Halides <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; DPhil 1971-74&nbsp; Sputtering Patterns from Electron Irradiated Alkali Halides
+
AH Khayrat     MPhil 1990-92         P D Townsend           TL and temperature gradient effects in microcline
  
−
K G Harrison DPhil 1969-71 M W Lucas Beam Foil Electron Spectroscopy
+
MR Khanlary     DPhil 1989-92                    P D Townsend            Luminescence of selected insulators and optical fibres
  
−
<br>H J Pabst DPhil 1969-73 D W Palmer A Channelling Study of Defects in Silicon
+
LS Babsail     DPhil 1989-92         P D Townsend            Formation of optical waveguides and SHG by ion
 +
implantation
  
−
<br>A H G El Dhaher MSc 1969-70 D W Palmer A 60 kV Accelerator System for Low Energy Channelling Studies
+
MJ Rodman       DPhil 1990-93         P D Townsend          Characterization of ion implanted optical waveguides
 +
in selected laser crystals
  
−
N M Khan DPhil 1970-74 M W Lucas Charge Exchange to the Continuum in Single Crystals
+
N Hamelin     DPhil 1990-93         P D Townsend          SHG in ion implanted waveguides
  
−
T C Ang MSc 1970-71 P D Townsend &amp; A R Bayley Colour Centres in Silica induced by Ion&nbsp; Implantation
+
M Houe     MPhil 1992-94         P D Townsend           Thermal domain reversal of LiNbO3 for SHG
  
−
<br>Y Al Jammal MSc 1971-72 P D Townsend Electron Produced Sputtering of Alkali Halides<br> DPhil 1972-75? <br>
+
N D Skelland     DPhil 1990-94         P D Townsend           High temperature ion implantation into insulators
  
−
T F Bartley MSc 1971-72 M W Lucas Measurement of Equilibrium Charge-Fraction Ratios of H<sup>+</sup> , H<sup><sub>2</sub>+</sup> and H<sup><sub>3</sub>+</sup> Ions in Carbon Using Continuous Channel Electron Multipliers
+
DE Hole                 DPhil 1991-94         P D Townsend          Optical effects of ion implantation into glass
  
−
D Bean MSc 1971-72 L Holland The Cleaning of Silicate Glass Surfaces in a Radiofrequency Discharge
+
G Kakarantzas     DPhil 1991-94         P D Townsend          Ion implanted waveguides in laser glasses
  
−
<br>J P Davies MSc 1971-2 D W Palmer An Investigation of the Channelography Technique
+
N Can     DPhil 1991-95         P D Townsend          Studies of ion implantation into insulators using
 +
nuclear methods, luminescence and waveguide
 +
techniques
  
−
<br>G G W Durbin MSc 1971-72 J A Venables Low Temperature Observations of Li and Na in the Scanning Electron Microscope
+
J R Ayres                          DPhil          1992-95                  D W Palmer              Electrically Active Defects Associated with
 +
                                                                                                S D Brotherton (PRL)    Dislocations and Grain Boundaries in Silicon
 +
                                                                                                                                                                                                                   
 +
DRR White     DPhil 1992-95         P D Townsend          Spectral luminescence studies of rare earth doped CaF2
 +
and some synthetic minerals
  
−
<br>J M Gilkes MSc 1971-72 P D Townsend Spectral Investigation of the Thermoluminescent process in LiF
+
S J Hartnett                      DPhil            1992-96                  D W Palmer                Uniaxial Stress / DLTS Studies on Deep Level Defects
 +
                                                                                                                                      in n-GaAs                                       
 +
                                     
 +
AH Jazmati     MSc 1994-95         P D Townsend           Luminescence of pure and doped thulium barium
 +
fluoride
  
−
<br>G W Nielsen MSc 1971-72 M W Thompson Rutherford Scattering from Metals<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; DPhil 1972-76&nbsp; A Rutherford Backscattering Study of Heavy Ion Ranges in Polycrystalline Aluminium and Amorphous Silicon
+
BJ Fonrobert     MSc 1994-95         P D Townsend          The photorefractive effect in BGO waveguides
  
−
<br>R R Armstrong MSc 1972-73 D W Palmer Channelography of Thin Metal Foils
+
F Lamouroux     MSc 1994-95         P D Townsend          Spectrometry measurements of glasses used for optical
 +
Waveguides
  
−
<br>P Barlow MSc 1972-73 M J Makin Irradiation Damage Studied by High Voltage <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; DPhil 1973-75 J A Venables Electron Microscope
+
MD Bateman     DPhil 1992-95         P D Townsend         The chronology of coversand deposition in Britain
  
−
<br>P Chandler MSc 1972-73 R S Nelson &amp; P D Townsend Surface Studies Using Ion Bombardment<br>
+
U Fritz                                MSc           1992-93                  D W Palmer
  
−
<br>J D Lee MSc 1972-73 A E Hughes &amp; P D Townsend Radiation Damage in Electrical and Optical &nbsp; Components
+
SG Raymond     DPhil 1993-95         P D Townsend           Luminescence of BGO (2:3)
  
−
B T Meggitt MSc 1972-73 M W Lucas Charge States of Hydrogen Atoms Traversing Foils
+
A Canimoglu                      DPhil          1994-97                  D W Palmer                Studies of Lattice Defects in As-Grown and
 +
                                                                                                                                      Irradiated n-InP
  
−
I I Sheikh MSc 1972-73 P D Townsend Thermoluminescence Defect Studies in Lithium Fluoride
+
S Hallensleben     MSc 1995-96         P D Townsend           Luminescence of ion implanted Eu in sapphire and
 +
Er in silica
  
−
J P Summers MSc 1972-73 B L Eyre &amp; J A Venables Electron Microscope Studies of Self-Ion Damage in Copper
+
SA Holgate     DPhil 1993-96         P D Townsend          Luminescence studies of fluorides, glasses and ZnS
  
−
R E J Watkins MSc 1972-73 G Dearnaley &amp; M W Thompson Radiation Enhanced Diffusion in Metals <br>
+
X Huang     DPhil 1994-97         P D Townsend          Ion implanted optical waveguides and laser ablated
 +
Bragg waveguide gratings
  
−
<br>P Barker MSc 1973-74 D W Palmer Proton Irradiation of Germanium
+
J Merbay     MSc 1996-97         P D Townsend          Surface analysis of float glass using
 +
cathodoluminescence
  
−
<br>S Datta MSc 1973-74 A E Hughes &amp; P D Townsend Luminescence Dosimetry using LiF<br>
+
I Okur     DPhil 1995-98         P D Townsend           Waveguide and optical studies of insulators using ion
 +
  implantation
  
−
S E Donelly MSc 1973-74 R S Nelson Diffusion of Inert gases in Metals
+
AP Rowlands     DPhil 1995-98         P D Townsend          Thermoluminescence detection of phase transitions:
 +
their effects and applications
  
−
<br>D W Garlant MSc 1973-74 P D Townsend Luminescence During the Sputtering of Alkali Halides
 
  
−
J W Muncie MSc 1973-74 B L Eyre &amp; J A Venables Proton Damage in Metals Studied by Electron Microscopy
+
C Deibel     MPhil 1997-99         P D Townsend          Laser annealing of copper and silver colloids in fused
 +
quartz
  
−
R Bin Jaya MSc 1974-75 J A Venables Use of the Scanning Microscope to Obtain Crystallographic Information
+
A Burkhardt     MPhil 1997-99         P D Townsend            Effects of applied fields during annealing of metal
 +
nanoparticles
  
−
M Brown MSc 1974-75 D W Palmer &amp; H J Pabst Computer Simulation Calculation of Proton Damage in Silicon<br> <br>A Majoubi MSc 1974-75 P D Townsend Sputtering of Alkali Halides
+
VA Smith     MPhil 1997-99         P D Townsend           Cathodoluminescence of silicates
  
−
<br>A Nyaiesh MSc 1974-75 M W Lucas Stopping Power for Protons and Molecular Hydrogen Ions
+
M Fleischer     MSc 1998-99         P D Townsend          Wavelength resolved image integration for
 +
luminescence applications
  
−
P Goode MSc (part time) 1972-75 G Dearnaley Study of the Effects of Ion Implantation on the Thermal Oxidation of Nickel
+
        A K Jazmati     DPhil 1996-99         P D Townsend          Optical properties and laser induced fluorescence from
 +
BGO:RE waveguides
  
−
R W Cranage DPhil 1972-75 M W Lucas Absolute Cross sections for Charge Exchange to the Continuum
+
NA Gallen     DPhil 1995-99         P D Townsend          Ion implantation waveguide formation in transition
 +
metal doped insulators
  
−
I Reid DPhil 1971-76 M W Thompson Sputtering Processes in Gold
+
T Karali     DPhil 1996-99         P D Townsend          Luminescence of rare earth doped dosimeters
  
−
<br>S D Mukherjee DPhil 1973-76 D W Palmer A Study of Proton Channelling and Dechanneling in MgO
+
S Hallensleben     DPhil 1996-99         P D Townsend            Enhanced sensitivity and speed in photomultiplier
 +
Tubes
  
−
A P Webb DPhil 1973-76 P D Townsend Refractive Index Changes Produced in Silica by Ion Implantation
+
G Vazquez     DPhil 1997-2000         P D Townsend           Advances in quality of optical waveguides on
 +
Nd:YAG and LiNbO3
  
−
<br>B Cephalas MSc 1976-77 P D Townsend Temperature Effect on Refractive Index Changes Formed by Ion Implantation
+
SW Harmer     DPhil 1997-2000         P D Townsend           Enhanced absorption photocathodes
  
−
M Wintersgill DPhil 1974-77 P D Townsend Luminescence in LiF: Mg: Ti
+
R Brooks     DPhil 1998-2001         P D Townsend           Ion beam luminescence of materials
  
−
R Strong DPhil 1974-77 M W Lucas Electron Loss From Light Ions
+
M Al-Maghrabi      DPhil 1998-2001         P D Townsend          Thermoluminescence spectra from sulphates, fluorides
 +
and garnets doped with rare earth ions
  
−
<br>R E Kaim DPhil&nbsp;!974-77 D W Palmer Oxygen Locations and Oxygen-Defect Interactions in Ion Irradiated Niobium
+
V Ramachandran     DPhil 1999-2002         P D Townsend          Luminescence spectra of lead tungstate, spodumene
 +
and topaz crystals
  
−
P J Chandler DPhil 1974-77 P D Townsend Radiation Induced Fluorescence in Insulators
+
PJT Nunn     DPhil 2000-03         P D Townsend         Characterisation of potassium tantalate niobate
 +
waveguides formed by ion implantation and surface
 +
studies of Nd:YAG crystals
  
−
<br>P Barker DPhil 1975-78 D W Palmer A Study of Proton- Irradiation Damage of Germanium
+
RJ Downey       DPhil 2003-06         P D Townsend         Improvements in photomultiplier performance
  
−
S Ahmad D Phil 1976-80 M W Thompson Effect of Ion Mass on the Energy Spectra of Sputtered Gold Atoms
+
LA Valberg     DPhil 2004-07            P D Townsend         Low level light detection
  
−
H J Whitlow DPhil 1977-80 M W Thompson &amp; D J O’Connor Low Energy Ion Implantation of Silicon<br>
 
  
−
<br>Peter – this is as far as my records go. Can you find the rest?<br>
 
  
−
<br>
 
  
−
== First Known Destinations or Employers of Graduate Students (1965-75)  ==
 
  
−
Adam Hilger Scientific Publishing <br>AERE Harwell<br>Bell and Howell Ltd<br>Birmingham University<br>British Cellophane Ltd
+
First Known Destinations or Employers of Graduate Students from the initial group of 1965-75
  
−
ESSO Research Labs UK<br>FOM Research Institute, Amsterdam, Netherlands  
+
Adam Hilger Scientific Publishing
 +
AERE Harwell
 +
Bell and Howell Ltd
 +
Birmingham University
 +
British Cellophane Ltd
 +
FOM Research Institute, Amsterdam, Netherlands
 +
Hospital Physics Dept at St Luke’s Hospital Guildford
 +
Imperial College London
 +
Kent University
 +
National Radiological Protection Board
 +
National Westminster Bank
 +
Research Labs of Gillette Industries
 +
Riverina College, NSW, Australia
 +
Salford University
 +
Surrey University
 +
Sussex University
 +
UKAEA Dounreay,
 +
University of Islamabad, Pakistan
 +
Voluntary Service Overseas
 +
Warwick University
 +
York University
  
−
Gillette Research Labs UK <br>Hospital Physics Dept at St Luke’s Hospital Guildford <br>Imperial College London<br>Kent University<br>National Radiological Protection Board <br>National Westminster Bank<br>Research Labs of Gillette Industries <br>Riverina College, NSW, Australia <br>Salford University<br>Surrey University<br>Sussex University<br>UKAEA Dounreay, <br>University of Islamabad, Pakistan <br>Voluntary Service Overseas <br>Warwick University<br>York University
+
5 Students went to positions in industry from this Sussex MSc
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10 students went on from the Sussex MSc to a Sussex DPhil and
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7 to PhDs elsewhere
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2 went from this Sussex DPhil to postdoctoral positions at another university
  
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5 Students went to positions in industry from this Sussex MSc <br>10 students went on from the Sussex MSc to a Sussex DPhil and <br>7 to PhDs elsewhere <br>2 went from this Sussex DPhil to postdoctoral positions at another university (Ahmed, Browning +&nbsp;?)
 
  
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<br>
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Posts held by Alumni by 2010 (where known)
  
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<br>Posts held by Alumni in 2010 (where known)  
+
Laila  Abu-Hassan Professor of Physics in University of Jordan and head of department
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Shoaib Ahmed, Board member Pakistan Atomic Energy Agency
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Ahmed Al-Ghamdi  Physics department, Vice Dean of Research, King Abdulaziz University Saudi Arabia
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Yahya Al Jammal      Professor in Physics in Mosul University, Iraq
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Mufied Al-Maghrabi Associoate Professor Physics, Hashemite University of Jordan
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Dia Arafah Professor of Physics, chairman of dept, The University of Jordan
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Hanafi Atan  Prof of Physics at The University of Sains, Malaysia
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Laila Babsail Ass Prof Physics, King Saud University
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Mark Bateman  Reader in Quarternary Paleoenvironments, Dept of Geography, Sheffield University
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Robert Brooks Industrial electronics and optical engineer, Sussex
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Raymond Browning    Worked in the University of York 
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Nurdogan Can, Professor, head of physics, Science dean, and pro Vice Chancellor Celal Bayar University, Turkey
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Peter Chandler      Director of medical software company
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Gordon Chapman  returned to a University in Australia
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R Cranage                  Hospital physics
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Graham  Crittenden    Worked in Dounreay, now active in Scottish Butterfly conservation
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Ross Downey Gardening
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Ahmed Faik Assoc Prof Computer Science and Engineering Johnson Smith University North Carolina
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Stuart Harmer Lecturer Manchester Metropolitan University
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Nicholas Hartley  European Commission (Science) Brussels
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Abdul Jazmati Atomic Energy Commission of Syria, Damascus, Syrian Arab Republic
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Alan Marwick, Consultant in computer systems in New York after retiring from senior positions with IBM
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A Mahjoubi    returned to academia in Iran
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Sebastian Hallensleben  Solysis, his company covers a range of scientific consulting
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Nicolas Hamelin The Research Cooperative, operating from Morocco
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Kevin Harrison      Harwell after a spell at FOM, Amsterdam
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Peter Haycock Professor of Physics in Keele University
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David Hole Senior research in Engineering at Sussex University
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Sharon Holgate Science writer, TV and radio science presenter
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Xuefeng Huang Tulane University USA and Scientific computing for Ericcson in Texas
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Robert Kaim ATMI Connecticut USA
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N M Khan      Owns his own company. Surface Engineering, in UK.
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Mohammed Khanlary Physics department Imam Khomeini International University in Iran
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AH Khayrat University of Birmingham
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Turgay Karali Associate Professor in Physics, Ege University, Turkey
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Francesco Lama Physics teacher in Oxford
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Stephen Lax Senior lecturer Communications Technology University of Leeds
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Bradley Luff             Kotura Inc Monterey California
 +
Patricia Nunn Retired
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Ibrahim Okur Professor Sakarya Universitesi, Fen Edebiyat Fakultesi, Fizik Bolumu, Mithatpasa, Adapazari, Turkey
 +
Heine Pabst        Deceased 
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Chris Perks  Technology manager Landauer Europe
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Vasuki Ramachandran Institute of Particle Science and Engineering, University of Leeds
 +
SG Raymond Post doc in New Zealand
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A A Rezazadeh          Professor of Electronics, University of Manchester / UMIST
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Matthew Rodman  Chemistry dept of Keele University
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Aled Rowlands  Geography lecturer in Aberystwyth University, private consultant and TV and radio science presenter
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Willy Siyanbola Leader of NACETEM Obafemi Awolowo University, Ile-Ife, Nigeria.
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Neil Skelland Research in QinetiQ  (Atlas Electronik UK)
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Victoria Smith  Laser ranging in Herstmonceaux
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Julie Strain Senior engineer of Intel (deceased)
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R Strong  Radiation Safety at Windscale
 +
Lin Zhang  Professor of Electronic Engineering in Aston
 +
Leo Valberg Market risk analyst at RBS, London
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Gloria Vazquez Lecturer in Physics, Leon University,  Mexico
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Robert Watkins          Aerospace engineering I Physics department of Oxford University   
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Harry Whitlow, Professor of Applied Materials, Lund University, Sweden and Jyvaskyla University, Finland.
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Alan P Webb    Electronics industry manager in Plessey (retired)
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Mary Wintersgill Professor and head of physics department Annapolis Naval Academy
  
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Shoaib Ahmed, Board member Pakistan Atomic Energy Agency<br>Harry Whitlow, Professor of Applied Materials, Lund University, Sweden and Jyvaskyla University, Finland.<br>Alan Marwick, consultant in computer systems in New York after retiring from senior positions with IBM<br>John O'Connor, Professor and is Head of the Physics Department,&nbsp; Newcastle University, NSW Australia
 
  
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Ian Wilson, formerly Dean of Engineering, Chinese University of Hong Kong <br>
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The preceding is only a partial list and more details, updates, and addition of data for uncited students would be welcome.
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We would like details for the following
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C Foster
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Z Sumengen 
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B Stocking 
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M Kidd 
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D Richards 
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T G Williams
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D J Elliot   
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S Harbinson   
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P J Mac Donald   
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A H G El Dhaher     
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T C Ang       
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T F Bartley               
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D Bean       
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J P Davies   
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G G W Durbin         
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J M Gilkes       
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S D Hartnett
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G W Nielsen   
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R R Armstrong 
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P Barlow     
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J D Lee     
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B T Meggitt       
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I I Sheikh         
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J P Summers       
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P Barker           
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S Datta       
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S E Donelly   
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D W Garlant           
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J W Muncie       
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R Bin Jaya   
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M Brown       
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A Nyaiesh     
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P Goode       
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I Reid         
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S D Mukherjee   
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B Cefalas       
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P Barker     
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KI Ahmed
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EK Glavas
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DA Parks
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RA Wood
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M Houe
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G Kakarantzas
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DRR White
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BJ Fonrobert
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F Lamouroux
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J Merbay
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C Deibel
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A Burkhardt
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M Fleischer
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NA Gallen
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          and others.

Revision as of 11:12, 9 August 2011

Particle-Solid Interactions

A History of the Particle-Solid Interactions Research Group
in the School of Mathematical and Physical Sciences
at Sussex University

Origins

n the early 1970s there was a group of five academic staff in the School eager to learn more about particle-solid interactions. They had by then equipped themselves intellectually and with the machines of experimental physics to carry out research in this field in a systematic way with projects that would fill in gaps in current knowledge. Around them students had clustered who were learning how to carry out research and enlarging their own understanding of the physical sciences. These students were attending lectures, reading and carrying out original experiments. The group had attracted postdoctoral fellows pursuing the more advanced topics and distinguished academic visitors, often from overseas, wishing to gain experience at Sussex and, perhaps, to build collaborative projects with their own groups. Altogether there were about 30 people involved in the group at any time in the mid 1970s.

A decade earlier four of these five were themselves postdoctoral fellows doing advanced research overseas alongside leading scientists of the day. To name them, Derek Palmer was in the Ecole Normale Supérieure, Paris, Mike Lucas was in the Argonne National Laboratory in Illinois, John Venables was in the University of Illinois at Urbana and Peter Townsend was in the Brookhaven National Laboratory in New York State. The fifth man was Michael Thompson, occasionally to be found visiting these labs and others like them, sometimes extending his visits over many months to engage in collaborative research. His first job after graduating in 1953 had been in the Atomic Energy Research Establishment at Harwell, but then in 1965 he was appointed to a Chair of Experimental Physics in Sussex. At Sussex he was warmly welcomed by John Venables, who had earlier returned from Illinois to a Lectureship in Physics, and by Robert Cahn who had been appointed to the Chair of Materials Science in the School of Applied Sciences and had himself worked in Harwell.

Another member joined the group shortly afterwards. His name was Barry Farmery and he had worked with Michael Thompson at Harwell in building accelerators and running experiments. At Sussex he became responsible for installing and operating the accelerators, managing a team of technicians, giving advice on the use of ion beams and frequently becoming involved as a respected collaborator in experiments.

The historical context of British science in the 1950s and 1960s is of relevance to this history because each member had graduated from a British university. After the Second World War the country had its ancient universities and it had the late-Victorian civic universities. All had increased in size only to the point where about 5% of pupils leaving school could go on to university education. The country in response to military needs had created vast establishments for research and development in aviation, jet propulsion, electronics, radar, chemical and biological weapons and atomic weapons. Besides this there were peaceful needs being met in large central laboratories, for example in medical research, telecommunication, public health and the newest was in atomic energy. To exploit discoveries many large industrial companies had their own research and development laboratories. By the mid 1950s the policies of the government were to shift some work from their own labs to those industries or, if the research was of a more fundamental kind, encourage the universities to take it on. But if none of the three wished to fund a topic it would be closed down.

The government had also recognised a shortage of university places, firstly because the wartime recruits into military service returned as civilians wishing to take up the higher education they had missed and secondly because of the wishes of school-leavers in a burgeoning population of young people. A committee of enquiry chaired by the eminent educationalist Lord Robbins recommended that higher education should be open to all with the ability to benefit from it. The implication was that the State would pay, in grants to the universities and grants to the students for their fees and maintenance. It was decided, momentously, to accept this doctrine, to expand existing universities and establish six new universities of which Sussex was one.

The policy on government labs had meant for young graduates aspiring to research that places like Harwell would be less likely to employ them. On the other hand the British universities had been full. It had seemed that careers for young British scientists might better be pursued in America. Four of this group had already gone overseas to work and could well have stayed. The fifth was looking at an attractive US offer and wondering whether to emigrate. But now the new university policy changed the prospect and the UK was on offer too. So it was that the group was enabled to form.


Themes

The group could have had several labels that included: ionising radiation in matter, or atomic collisions in solids, or radiation damage and defects in solids, to give but three examples. But to catch up as many themes as possible without writing a paragraph ‘Particle-Solid Interactions’ had to do and that was what the group called itself for a visit by an assessment panel of the Science Research Council in 1975.

Some paragraphs follow in which the interests of the five members of the group are summarised. Each knew that he could not cover every aspect of knowledge in such a broadly defined field but would devise experiments and theories to fill interesting gaps in his own knowledge. If that gap might also be of interest to another member of the group it might be given priority, or collaboration might develop or a project might transfer from one member to another.

The group united around a willingness to share interests, a desire to explore zones of scientific ignorance and to map them for others to follow. One way that unity found expression was in regular seminars attended by staff and students where someone would talk about the current state of their research and expect discussion. Whatever its breadth of interest the scope of the group’s research was limited by equipment, for it had built or purchased a set of tools that could serve some purposes but not others. The members also had options to use equipment elsewhere, but by 1975 it was unlikely that they could add much to those expensive resources. Their particle toolkit included two electron microscopes, a 20kV pulsed ion accelerator for heavy ions, a 300kV ion accelerator and a 3MV van de Graaf accelerator, for ions or electrons, housed in a specially shielded building. Later, a small 45kV ion implanter was added. This was followed in the 1990’s by a high current 200 kV implanter which was mostly used on a commercial project to explore changes in the surface properties of glass in areas as diverse as production of car mirrors, anti-reflective coatings and reflective sunglasses.


Scientific Interests

The fundamental scientific question for the group was how are the structure and properties of condensed matter affected by an environment of ionising radiation? That question grows upon roots in the technologies of electronics, nuclear energy and medicine. Besides the intrinsic scientific value of the answers, applications were inferred that could benefit everyone.

The impact of ions upon a surface in a vacuum has a bad history of spoiling the performance of electrical machines. For example vacuum devices like fluorescent tubes for lighting and electron tubes for television are spoiled by atoms being sputtered by ion impact from electrodes and condensing inside the tubes to prevent light from being emitted. The newer solid-state devices in electronics or power engineering are made of semiconductor crystals whose electrical conductivity is engineered by creating defects (eg. by adding minute concentrations of phosphorous to silicon to make a dilute alloy) But if the device is exposed to ionising radiation crystal defects may be created that could inhibit its performance. Paradoxically, ion impact can have effects that create technical opportunities. The bad guy appears to be good in processes for making modern microcircuits like sputtering, ion implantation and radiation damage.

In the development of nuclear energy for peaceful purposes it was soon discovered that the useful life of reactor materials is limited by radiation damage. In fission reactors fuel rods swell, ductile metals become brittle and by storing energy graphite moderators might unexpectedly overheat. Fusion reactors have similar problems but in addition atoms are sputtered by particle impact from their internal walls which may inhibit the desired fusion. In 2010 the technology of atomic energy still needs research into these effects as the third generation of fission reactors and the first generation of fusion reactors are being built.

The early style of experimentation in nuclear science was to irradiate a sample with neutrons in a reactor and take this back to the lab for measurement or, with more difficulty, do the measurements inside the reactor. But at Harwell in 1958 a ground-breaking move had been made when a small accelerator of heavy ions was built to simulate irradiation by neutrons. Argon ions having energies of 50 keV bombarding a sample of copper will produce the same sort of atomic recoils as 2 MeV neutrons and the experiments become better controlled and easier to analyse. For example one could create damage in thin crystals that could be seen as disordered regions in an electron microscope. Or atoms sputtered from the crystal surface could have their distribution of energy analysed knowing that this carries information about collision cascades inside the irradiated solid.

In both semiconductors and metals many valuable experiments on radiation damage had been done in the 1950s and 60s with MeV electron beams from accelerators, but the new heavy ion accelerators opened a new door. In addition to damage to the structure they could also implant ions of another chemical element and a new way of making dilute alloys was invented. It had the attractive new feature of being able to implant to a depth that was controlled by the ion energy. Entirely new classes of electronic device followed, as did metal surfaces with increased resistance to wear.

When the group of five assembled in Sussex during the 1960s some of these things had just been done at the places they came from. But prospects were open and many ideas were left to be explored. To show how the mosaic of members’ interests made a picture and how the borders and gaps in that picture became places for conjecture or research, a brief summary of the achievements and interests of the five academic leaders follows below.

John Venables, who arrived in 1963, had contributed for some years to the study of crystal defects and crystal growth by the diffraction of an electron beam in an electron microscope. Because defects perturb the diffraction process the image of crystal in the microscope can show their position and may even allow their structures to be resolved. At high enough energies the electrons of the microscope beam can themselves produce radiation damage whose structures may be studied in the same instrument.

It was a powerful technique and especially so because John Venables had modified his microscopes, uniquely, to permit the sample to be cooled to very low temperature, bombarded with low energy ions to create visible defects, or have vapours condensed upon it. Major contributions were being made by his students by 1975 to our understanding of the processes by which a vapour condenses into a crystalline film upon a crystalline substrate where, initially very thin mono-layers of atoms cover the entire surface then thicker islands form whose growth is fed by diffusion from the mono-layer.

Michael Thompson arrived in 1965 having studied at Harwell the way in which the kinetic energy of a particle creates defects in the solid. It can do this through a cascade of atomic collisions spreading out from the point of impact or the ionisation around the particle track. A related effect is the kinetic sputtering of atoms through the surface that could be studied by measurement of their momentum. That is to say that one measures both the angular distribution and the energy distribution. A pulsed ion beam and a time-of flight apparatus had been devised for this purpose. Theoretical work on the statistics of collision cascades and the effect of the surface upon the emerging atoms led him in 1967 to a formula E/(E + Eb)3 for the energy distribution and this was being found in many experiments ( Eb is the binding energy of an atom to the surface). It is often referred to as the Thompson formula in the literature. From the fact that the distribution becomes like 1/E2 when E >> Eb one infers that the number of atoms permanently displaced from their sites by a collision cascade must be proportional to the energy in the first collision. This is a result of great importance in radiation damage. Departures from this sputtering formula were being discovered in the case of very energetic and heavy ions or in the case of single-crystal targets. These were hot topics in 1975 that revealed the presence of literally hot spots around the site of the collision cascade, and showed how the crystal structure itself imposes structure upon the cascade.


In the early 1960s a related phenomenon had been discovered called channelling. In this a particle entering a crystal in a direction close to a prominent crystal axis and on a trajectory that entered the surface in the spaces between the atomic rows that define that axis, travelled long distances bouncing back and forth amongst those rows. It was manifested by exceptional ranges of ions of any mass when their beams were aligned within some critical angle of an axis. This angle was typically a few degrees and proportional to [Z1Z2/E]1/2 , here Z1 and Z2 are the atomic numbers of particle and solid respectively and E is the particle’s kinetic energy. The penetration experiments with light ions had been done at Harwell by Michael Thompson and his colleagues, the heavy ion penetration by a Canadian group led by John A Davies and the theory of the critical angle came from Denmark’s Jens Lindhard. The effect of channelling was also seen in the reflection or back-scattering of ions where minima were seen in the reflected fraction of the beam whenever the beam was aligned with either rows or planes. There was then both axial and planar channelling and many groups entered into the study of this phenomenon and its applications. High energy electrons and positrons were joined in too.

In a side-shoot of this field Michael Thompson had scattered ions at grazing incidence from the flat surface of a crystal whilst on a visit to Canada. A significant number were reflected as if by a mirror – the ion’s momentum perpendicular to the surface being reversed -. His students were studying this process further and devising means by which the structure and composition of surfaces could be determined. The theory of channelling was also to be refined by these observations and linked to experiments, about to be described, by one of Derek Palmer’s students.

Michael Thompson’s interest in the penetration of heavy ions into the solid was being pursued in 1975 by a student measuring the distribution of depths below the surface at which these ions lodged. The method used was to back-scatter MeV H+ or He+ ions into an energy sensitive detector and from their energy distribution unfold the depth distribution. The species of heavy ion was varied, or the kinetic energy, or the angle of incidence. From the data of many such experiments it was hoped to test and refine theories current at that time or at least provide empirical data for technology.

Derek Palmer’s interests were mainly in irradiation effects and defects in crystalline semiconductors, but he studied also irradiation-induced defects in the body-centred metals iron and niobium. The former had great practical importance for electronic devices and the latter provided valuable information relating to nuclear-reactor technology. He showed how to use channelling of MeV protons and helium ions, in association with Rutherford back scattering and proton-induced and 3He-induced nuclear reactions, as an analytical tool to detect defects created by radiation damage or ion implantation and to analyse their structures and properties. A valuable fundamental feature, exploited in the work, of irradiation by light energetic ions is that the main ion-atom collision process is via nuclear-nuclear Coulomb interactions, and therefore that most of the collisions create lattice defects that are simple interstitials and vacancies. Clear comparisons with electron-irradiation studies elsewhere could thence be made.

An important innovation in the work by Derek Palmer was his setting up, on a beam line of the 2.0 MV Van de Graaff ion accelerator, of an experimental facility that allowed angle-resolved ion-channelling, in-situ irradiation and property measurement of semiconductor and metal samples at temperatures down to close to 4K. That facility allowed irradiation-induced defects to be investigated before their thermally induced diffusion. Changes in the defect structures caused by heating were then studied in detail. For semiconductors, his investigations demonstrated that ionisation by fast (200 keV to 2.0 MeV) light ions could damage the lattice structure in silicon and germanium, additional to the disruption due to the nuclear-nuclear elastic collisions. Examples of particular results for metals (in work supported in part by AERE, UK) were the findings that the lattice sites of molybdenum atoms dissolved in iron and of oxygen atoms in niobium could be changed by their trapping of irradiation-induced point defects, and that that also allowed quantitative investigation of the thermally induced mobilities of the defects.

The phenomenon of channelling had been earlier studied by Derek Palmer in crystals of quartz. With a student he was in 1975 unravelling the fine detail of how channelled trajectories in another oxide crystal MgO change their direction from inter-axial to inter-planar. It is a process called scattering in the transverse plane, where this plane is perpendicular the crystal axis concerned, in which patterns emerge which can focus trajectories upon certain rows of atoms. This was being related by Derek Palmer’s student to the surface-scattering experiments of Michael Thompson and his students.

It became clear, however, that the ion-channelling technique was not sensitive to the very low concentrations of lattice defects that could strongly affect the crucial electrical properties of semiconductors, and so Derek Palmer’s research moved into use of the DLTS (“Deep Level Transient Spectroscopy”) technique that investigates defects by their trapping and emission of electrons and holes in the semiconductors. Again the creation and properties of irradiation-induced defects at both cryogenic and higher temperatures needed to be investigated, and an in-situ DLTS cryostat was designed and was installed on a further ion-beam line of the Van de Graaff accelerator. Because the use of proton-irradiation-induced defects to produce high resistivity regions in GaAs devices and integrated circuits was of much technological interest, Derek Palmer developed a close research link with the Philips Research Laboratory at Redhill, and he and his research students made detailed in-situ DLTS and associated electrical investigations on lattice defects in GaAs and on the related alloys Al(x)Ga(1-x)As and In(x)Ga(1-x)As. Indium phosphide was also of industrial interest, and DLTS investigations of light-ion created defects in that semiconductor were made in later work. The work on GaAs etc and on InP produced valuable new results for irradiation-induced defects concerning their electronic energy levels, their thermal annealing properties and their natures.

The experimental ion-irradiation / DLTS facility was subsequently supplemented by a rig that allowed in-situ uniaxial stress to be applied to semiconductor samples at temperatures down to about 10K before and after proton and helium ion irradiations. The studies on n-type GaAs showed that uniaxial stress applied along the <100> and <110> crystallographic directions splits the electronic energy levels of each of the well known irradiation-induced defects E1, E2 and E3 into two levels of equal populations. Those experimental data showed that each of those lattice defects contains a single <111> crystallographic axis (ie, has C3v symmetry) and strongly suggested that E3 is an arsenic Frenkel defect, ie an arsenic interstitial-vacancy close pair, and that E1 and E2 may also be arsenic Frenkel pairs, but with different interstitial-vacancy separations. Those were the first ever uniaxial-stress studies on any irradiation-induced defect in GaAs.


Mike Lucas, before he joined the group, had worked on the properties of defects in metals after irradiation with neutrons. His new interest was in the disturbance of the electrons in a solid by a very fast moving ion. He passed his ion beam through a thin solid and detected the electrons that emerged from the surface. These had their momentum analysed and it was found, surprisingly, that downstream of the foil, in the exact direction of the ion beam, the most probable speed of the electrons was the same as the speed of the ions. It was a result of great interest to theoreticians, several whom joined our group as collaborators and became frequent visitors. A new theory of the collision processes that excite electrons around a particle track was developed. The process responsible for the electrons emitted at the speed of the ions was called ‘charge capture to continuum states’.

Peter Townsend had a broader interest in ionisation by radiation. He studied insulating solids that were often crystalline, sometimes glassy and nearly always transparent. Optical properties and their relationship to crystal defects is a recurring theme in his publications (e.g. Can one tailor optical properties?). He had just made a major contribution to theories of radiation damage by studying the creation of defects and sputtering of ions from ionic crystals like potassium iodide by irradiation with slow electrons. The electrons lacked the momentum to displace an atom by direct collision Even more surprising had been his prediction and demonstration that even ultraviolet light could sputter ions from the surface. The model correctly explained why the sputtering patterns of alkali and halogen ions were different. The theory of this process was a fascinating example of the radiation exciting an electron and this potential energy being transferred into kinetic energy on the nucleus of a single ion.

The phenomenon of thermo-luminescence was another of Peter Townsend’s interests, especially when related to defects that could be introduced by radiation or by ion implantation. Crystals like lithium fluoride, which have important uses as radiation dosimeters in medicine and radiological protection, were being studied in 1975 and he built equipment to measure the emission spectra. This information was lacking from most other thermoluminescence research groups. As a consequence, Sussex stayed in a lead position in this field for the next 30 years. In the late 1990’s this same type of equipment opened a novel route to detection of phase transitions, both of crystals and nanoparticle inclusions.

A third group of Peter Townsend’s experiments used high energy ions to damage the structure of glasses in a controlled layer beneath the surface. The depth of the layer was made comparable to the wavelength of light and he thus constructed optical waveguides. This work was to be of immense significance in developing the field of opto-electronics for smaller computers and optical fibres as transmission lines for telecommunication. It may be noted that Mike Thompson arranged a meeting with Charles Kao when Kao worked on this topic at the Standard Telecommunication and Cables Laboratories in the 1960s. At that point the potential of optical fibres had not been recognised by industry and the Sussex group were interested to see if ion implantation could be included in the processing. For the fibres this was not possible, but later, in 2009, Charles Kao received the Nobel Prize for Physics for making optical telecommunications possible. There was also some glory reflected on Sussex as this meeting prompted Peter Townsend to devise an ion implantation route to make optical waveguides in insulating crystals. This was a semi-universal route which has now been widely used in many more than 100 materials for waveguide lasers, non-linear optics and key items of modern photonics. Physics is a small community, as Townsend visited the Chinese University of Hong Kong in 1992 as the Wei Lun Professor whilst Professor Kao was Vice-Chancellor there.

A collaborative project was set up with Professor Cahn’s Materials Sciences group in the School of Applied Sciences. Rob Wilshaw used ion implantation of H+ ions to assist the fracture of quartz crystals under mechanical stress. It was shown that even at low energies the implantation softened the quartz significantly. In application, it was hoped that the effect might reduce the energy expended in the crushing of minerals in the mining industry (RTZ).


Postgraduate Teaching in the early years

In this section the titles of the lecture courses open to the graduate students lays out the subject matter of our interests. A full list of all the staff serving in the group up to 1980 is given in Appendix A. A detailed picture of the research and its development over time can be gleaned from Appendix B which gives the names of all the graduate students, the titles of their theses and the names their supervisors. The onward careers of those early students are indicated rather briefly, as for many of them, details of their later lives are frequently unknown. However, over the subsequent years many of the Sussex graduates from the ion implantation group have made significant contributions to Physics and Materials Science. Of those who stayed in Academic environments there are numerous Professors, Head of Department, Deans and Vice Chancellors.

The Physics Department taught all its research students in their first year enough additional physics to prepare them for their task. Short courses of lectures advanced their knowledge of quantum mechanics for example. More technical instruction was given to equip the students for using central computers, libraries and workshops. Where there were large enough groups to make it economical in staff time, specialised courses were given on that group’s subject, such as Condensed matter at low temperature, atomic and laser physics and particle-solid interactions.

In the latter our group developed an MSc course jointly with a group having similar interests at Salford University. It was entitled ‘Atomic Collisions in Solids’ and was described in its prospectus as follows:-

‘Atomic collisions in solids have attracted a great deal of attention in recent years. Processes such as atomic collision sequences and cascades, particle channelling, electron excitation and ion penetration are being studied in detail. The field has important applications in radiation damage, ion implantation, sputtering technology, electron microscopy, defect structures analysis and vacuum technology, many of which are basic to industrial processes. Modern advances have created a demand for education both from established scientists in Government and industrial laboratories and from new engineering and science graduates wishing to receive initial training. For the latter category over and above its intrinsic scientific value the subject involves a wide range of methods and techniques which make it an exceptionally valuable area for graduate training.’………….

…‘we offer a course beginning in October 1971, built upon a set of seven modules lasting about three weeks each. All of these could be taken individually by short term students whilst an approved selection of four, together with a project, will make a student eligible for an MSc award’…..

…..’while the majority of the tuition will be given by University staff we recognise that great expertise in this field resides in government and industrial research laboratories. We are therefore making extensive use of visiting professors from Harwell and invited speakers from industry.

In addition, the universities may permit an MSc student, in approved circumstances, to satisfy the project requirement by work carried out in an external organisation.’….

The titles of the modules were:-

‘1 Theory of the defect solid state and atomic collision processes 2 Radiation damage 3 Structural analysis of crystals 4Ion implantation 5 Ion beam technology 6 Composition analysis of solids 7 High vacuum and high voltage technology’

The course ran from 1971 to 1974. 33 MSc awards were made by Sussex University and a similar number by Salford. The Science Research Council provided some funding for approved students and this style of graduate course became a model that other universities followed.

Our DPhil students, as part of their initial course work, went through such modules as were appropriate to their research topic and some of the MSc students were offered the chance of continuing for the DPhil qualification. Even after the MSc course closed several of the modules continued for the DPhil coursework.

In appendix A we list all the Sussex staff members by category, academic, postdoctoral, technical and clerical; also the Salford academic staff, the visiting professors and the industrial collaborators who assisted in the supervision of Sussex students. This list includes those who were associated with the early course, and does not attempt to list the very many, and distinguished visitors who came to the group in later years.

In appendix B we list the Sussex graduate students with their years, the name of their supervisor and the title of their dissertation or thesis. This list is not confined to the initial years, but attempts to include everyone up to the 2010 when the accelerator group was finally closed. A summary of the initial employment from the early students and the current (2010) employment is noted where possible. We regret that the 2010 list is far from complete although many distinguished people are cited.


Overview of the initial Ion Implantation group at the time of Professor Thompson

How well did the Particle-Solid Interactions Group perform the mission it began in 1965? Certainly it played its part in proving that the new University of Sussex would be able to support research at an internationally recognised level and to win research grants in competition with long-established universities. In 1961 in some influential circles this had been doubted. This account gives a snapshot of the work in progress in one research group in the mid to late 1970s. But it was but one of many groups of equal distinction flourishing in Sussex in that period.

It must not be thought from reading this history that the five academic staff devoted all their energies to research and postgraduate teaching. Each of them carried a full share of university duties that included undergraduate teaching, examining and administration. The proportion of each activity was different for each of them. Was the content of their undergraduate courses changed by this research? Rather little one suspects, because the research results were usually too detailed to include in the wider curriculum. But the quality of their teaching and its effect upon their students probably was enhanced. Amongst the many reasons are first, the depth of reading that one does to support personal research deepens ones understanding of Physics in concept and in technique and that makes one a better teacher of the general subject. Second, the experiences of research sharpen one’s mind to make it more critical of information received, whether from one’s own experiment or the account of someone else’s. When that critical approach is transferred through teaching Experimental Physics to undergraduates they will learn how to judge information for themselves, not only becoming better physicists but also better citizens.

In the early formative years of the group at least 50 graduate students were awarded higher degrees as a result of work they did in this group. In direct ways they were taught how to do research and they were given substantial knowledge. But they also learned for themselves and in graduating proved that they knew how to explore further and to make their own maps of knowledge. From the careers that can be tracked it seems likely that the individuals’ prospects were enhanced by the time the spent here and the people the met. That should be the proper outcome to education at any level. But in addition one might note the evident utility of the research and the outcomes for the benefit of institutions both public and private and the lives of people in general.

The group and its development in later years

Undoubtedly the driving force of the initial implantation group was Professor Mike Thompson. Consequently the emphasis on the various topics changed somewhat when he moved into administrative posts at Sussex, and then left to become a Vice Chancellor of East Anglia and then on to Birmingham. His skill in these new tasks was recognised by a knighthood. Ion implantation however remained a key experimental focus for Drs Lucas, Palmer and Townsend and all three had a significant scientific output from the accelerator laboratory as well as their work in related areas of solid state and materials science.

The group of Professor Townsend built on their earlier techniques of optical effects of ion implantation and these were complemented by his laser, luminescence and thermoluminescence activities. There was considerable funding both from UK Research Councils, foreign industry and many European research programmes. Hence there were many effective collaborations and research visitors and students to the laboratory until its closure in 2010. A particularly key figure in the later years was Dr David Hole, who not only ran the 3MV machine, in close association with the experiments of Peter Townsend, but also had his own major programme with the JET laboratory on analysis of materials used in the development of Tokamaks. So, atomic energy was both at the beginning and at the end of the accelerator group’s research programme.

Monitors of success from the Townsend group included some 47 DPhil students and more than 20 MPhil and MSc degrees. Townsend was named the lead candidate for the Engineering section of the 2004 Descartes Prize on Excellence in Research for his work on improving photomultiplier tubes and their application for Optical Biopsy in breast cancer detection. In 2008 there was also a small celebration to note Townsend’s 500th publication. Subsequent Sussex publications from both Townsend and Hole are still emerging.

MWL, DWP, MWT and PDT January 2011


APPENDIX A

Key members of the ion implantation group joint programme

Staff University of Sussex University of Salford (collaboration 1971-75)

Professor M W Thompson, Prof. of Experimental Physics, (1965-80) Professor G Carter, Prof. of Physical Electronics Dr M W Lucas, Lecturer in Physics (1966-93) D G Armour, Lecturer in Electrical Engineering Dr D W Palmer Lecturer/Senior Lecturer (1966-98) Dr J S Colligon ,, Dr P D Townsend Lecturer/Reader/Professor (1966-2009) Dr W A Grant ,, Dr J A Venables ,, (1963- ) Dr F Paton ,, Professor R W Cahn, Prof of Materials Science (1963-80) Dr R Andrews ,, 

                                                                                                                                         Dr G Farrell                        ,,

Dr G A Stephens ,,

Associated visitors in the first few formative years of the group included Professor G Dearnaley, Visiting Professor, AERE Harwell Professor R S Nelson ,, ,, Dr B L Eyre, External supervisor, AERE Harwell Dr A E Hughes, ,, ,, Dr M J Makin, ,, ,, Dr P Blood ,, Philips Research Labs. Dr J Shannon ,, ,, 

The Research Fellows / Research Assistants (“RF/A”), local & visiting collaborators included the following: 
Dr S Alaya                                                          (1994, 1996, 1997)
Dr R A R Bayly,       RF/A, Physics                   (1970-73) 
Dr M Ben-Salem                                                 (1995, 1996) 
Dr P Combasson, RF/A, Physics                        (1976)
Dr C Comrie                                                        (1979-80)
Dr J O’Connor    RF/A, Physics                         (1979-81) 
Dr M Domkus                                                     (1982-83)
V A Dravin                                                          (1997, 1998)
Dr K H Ecker         RF/A, Physics                      (1971-73)
Prof. P C Euthymiou                                           (1992)

Dr G E Giakoumakis (1985, 1992) Prof. A A Gippius (1992) Dr A H M Husain (1983-84) Dr L Holland (1974-75) Prof J C Kelly (1967 & 1974) Dr A H M Husain (1983-84) Dr R E Kaim (1979) Prof. H Maaref (1993, 1995, 1997) Dr H J Pabst RF/A, Physics (1973-76) Dr A P Pathak Dr A A Rezazadeh (1982-84) Dr M Saidoh (1975-76) Dr A V Spitsyn (1981) Dr M A Subhan (1981) Dr T Taguchi (1979-80) Dr D Titley RF/A, Physics Dr V V Ushakov (1994) Dr D van Vliet RF/A, Physics (1967-70) Dr W Steckelmacher, RF/A, Physics (1974- ) Dr T R Wilshaw, RF, Materials Science (1968-71) Dr I H Wilson, RF, Physics (1965-68) Dr G Zardas (1987)

Mr B W Farmery, Experimental Officer in Physics Mr E Turpin, Technician Mr N Priestley ,, Mr D Hole ,, Mr A Houghton ,, Miss J Teare ,, Miss N Kingan Secretary (1965-69) Mrs M Tait ,, (1969 – )

A working pattern of having visitors, both senior and postgraduate student level became firmly established and Sussex has benefitted considerably from this strategy. Many senior people have visited with funding from SERC, EPSRC, The Royal Society, EC funding, or other travel grants. Additionally the links have involved visiting students to Sussex, both at the graduate and undergraduate level. A complete chronological list of such visits is difficult to reconstruct as it involves several hundred people, many of whom have visited on many occasions. The following list therefore is intended to be indicative of the pattern and only cites a very few of the more long term collaborations. From the viewpoint of publications the same visitors are frequently co-authors together with members of their own research groups. This global pattern of research is highlighted by a brief head count of co-authors, and their countries, of Peter Townsend. In about 2008 he passed the 500 publication mark and at that stage had some 450 co-authors from 42 different countries.

Mike Lucas had a long term collaboration with Prof K Dettmann at University of Freiburg-im-Breisgau Prof J Macek at University of Nebraska Prof K O Groeneveld at J W Goethe University, Frankfurt Dr. D H Jakubassa-Amundsen at University of Munich 

Derek Palmer had long term collaborations with
         Professor P C Euthymiou, University of Athens, Greece
Dr G E Giakoumakis, University of Ioannina, Greece 
         Professor A A Gippius, P N Lebedev Physical Research Institute, Moscow
Professor H Maaref, Université du Sud, Monastir, Tunisia

Barry Farmery started a research programme with Dr Paul Coad at the JET lab in Culham. This was then expanded by Dr David Hole until the accelerator closure in 2010. The research has been key to assessing the problems of materials damage and transport within the Tokomak fusion reactor vessel in JET. The programme and our equipment has now moved to Portugal to continue work for ITER.

Peter Townsend had a very fruitful collaboration with Southampton and University College London with work on laser waveguides and photonics; a collaboration since 1974 with many member of the Universidad Autonoma de Madrid which generated some 50 publications, for which he received a Doctor Honoris Causa; Visits from Professor Bairui Yang and her students from Beijing have been particularly effective in terms of thermoluminescence publications and development of a new field of optical detection of phase transitions; a 6 year collaboration with Societa Italiana Vetro provided considerable accelerator funding, many papers and patents, and detailed studies of optical effects of ion implantation in glass. A number of EC funded programmes have advanced Condensed matter work from Sussex, and in particular, spectacular advances in the performance of photomultiplier tubes. In their use for breast cancer detection this resulted in the group leading the 2004 Engineering section of the prestigious Descartes prize. There was also a long term collaboration (~35 papers) with Prof Helen Rendell combining luminescence measurements with geological and thermoluminescence dating and analysis. This interest expanded to include several other partners from Madrid and St Andrews.


APPENDIX B

A chronological list of postgraduate students from the research group from 1966 to 2010


Name Degree Dates Supervisor Title of Thesis

A D Marwick DPhil 1966-70 M W Thompson Channelling and Surface Scattering


C Foster DPhil 1966-70 I H Wilson Atomic Scattering and Interatomic Potentials 

                                                                                              M W Thompson

Z Sumengen MSc 1966-67 D W Palmer Channel Electron Multipliers as Detectors of 

                                                                                                                                      Electrons and Protons

G Chapman DPhil 1967-71 M W Thompson High Energy Sputtering


B Stocking MSc 1967-8 M W Lucas Measurement of the Surface Density of Thin 

                                                                                                                                      Foils

J D Haskell MSc 1967-8 D W Palmer

M Kidd MSc 1967-8 P D Townsend Topography of Sputtered Surfaces

D Richards MSc 1968-69 P D Townsend Sputtering Measurements of Silica and Sodium 

                                                                                                                                        chloride

T G Williams DPhil 1968-71 D W Palmer Ion Channelling and Irradiation Effects in 

                                                                                                                                        Gallium Arsenide

D J Elliot DPhil 1968-71 P D Townsend Low Energy Ion Irradiation in Alkali Halide 

                                                                                                                                        Crystals

N E W Hartley DPhil 1968-71 R W Cahn The Comminution of Minerals, some Fracture and 

                                                                                              T R Wilshaw                 Deformation Studies on Quartz with  reference to  
                                                                                                                                    Size Reduction

G S Harbinson DPhil 1969-73 M W Thompson X-Ray Production and Ion Scattering from 

                                                                                                                                     Surfaces

P J Mac Donald DPhil 1969-73 D W Palmer Ion Implantation in Germanium

G C Crittenden DPhil 1969- 73 P D Townsend Thermoluminescence in Doped LiF

R Browning MSc 1969-70 P D Townsend Defect Formation in Alkali Halides 

                                          DPhil            1971-74                             ,,                      Sputtering Patterns from Electron Irradiated    
                                                                                                                                     Alkali Halides

K G Harrison DPhil 1969-71 M W Lucas Beam Foil Electron Spectroscopy

H J Pabst DPhil 1969-73 D W Palmer A Channelling Study of Defects in Silicon

A H G El Dhaher MSc 1969-70 D W Palmer A 60 kV Accelerator System for Low Energy 

                                                                                                                                      Channelling Studies

N M Khan DPhil 1970-74 M W Lucas Charge Exchange to the Continuum in Single 

                                                                                                                                      Crystals

T C Ang MSc 1970-71 P D Townsend Colour Centres in Silica induced by Ion 

                                                                                               A R Bayley                    Implantation

        Y Al Jammal                      MSc             1971-72                   P D Townsend           Electron Produced Sputtering of Alkali  halides
                                               				                                                         
         T F Bartley                        MSc             1971-72                   M W Lucas                Measurement of Equilibrium Charge-Fraction  ratios
                                                                                                                                      of H+ , H2+ and H3+ Ions in Carbon using 
                                                                                                                                      Continuous Channel Electron multipliers

D Bean MSc 1971-72 L Holland The Cleaning of Silicate Glass Surfaces in a 

                                                                                                                                      Radiofrequency Discharge

J P Davies MSc 1971-2 D W Palmer An Investigation of the Channelography technique

G G W Durbin MSc 1971-72 J A Venables Low Temperature Observations of Li and Na in the 

                                                                                                                                        Scanning Electron Microscope

J M Gilkes MSc 1971-72 P D Townsend Spectral Investigation of the Thermoluminescent 

                                                                                                                                        process in LiF

G W Nielsen MSc 1971-72 M W Thompson Rutherford Scattering from Metals 

                                          DPhil           1972-76                           ,,                         A Rutherford Backscattering Study of Heavy  ion
                                                                                                                                       Ranges in Polycrystalline Aluminium and  
                                                                                                                                       Amorphous Silicon

R R Arstrong MSc 1972-73 D W Palmer Channelography of Thin Metal Foils

P Barw MSc 1972-73 M J Makin Irradiation Damage Studied by High Voltage 

                                          DPhil           1973-75                   J A Venables              Electron Microscopy

P J Chandler MSc 1972-73 R S Nelson Surface Studies Using Ion Bombardment 

                                                                                               P D Townsend

         J D Lee                              MSc            1972-73                    A E Hughes               Radiation Damage in Electrical and Optical 
                                                                                               P D Townsend               Components

B T Meggitt MSc 1972-73 M W Lucas Charge States of Hydrogen Atoms Traversing Foils

I I Sheikh MSc 1972-73 P D Townsend Thermoluminescence Defect Studies in Lithium 

                                                                                                                                       Fluoride

J P Sum rs MSc 1972-73 B L Eyre Electron Microscope Studies of Self-Ion Damage 

                                                                                               J A Venables                   in Copper

R E J Watkins MSc 1972-73 G Dearnaley Radiation Enhanced Diffusion in Metals 

                                                                                               M W Thompson

P Barker MSc 1973-74 D W Palmer Proton Irradiation of Germanium

S Datta MSc 1973-74 A E Hughes Luminescence Dosimetry using LiF 

                                                                                               P D Townsend

S E Donelly MSc 1973-74 R S Nelson Diffusion of Inert gases in Metals


D W Garlant MSc 1973-74 P D Townsend Luminescence during the Sputtering of Alkali 

                                                                                                                                       Halides

J W Muncie MSc 1973-74 B L Eyre Proton Damage in Metals Studied by Electron 

                                                                                               J A Venables                  Microscopy

R Bin Jaya MSc 1974-75 J A Venables Use of the Scanning Microscope to Obtain 

                                                                                                                                       Crystallographic Information

M Brown MSc 194-75 D W Palmer Computer Simulation Calculation of Proton 

                                                                                               H J Pabst                         Damage in Silicon

A Mahjoubi MSc 1974-75 P D Townsend Sputtering of Alkali Halides

A Nyaiesh MSc 1974-75 M W Lucas Stopping Power for Protons and Molecular 

                                                                                                                                        Hydrogen Ions

P Goode MSc (p/t) 1972-75 G Dearnaley Study of the Effects of Ion Implantation on 

                                                                                                                                         the Thermal Oxidation of Nickel

R W Cranage DPhil 1972-75 M W Lucas Absolute Cross sections for Charge Exchange to 

                                                                                                                                          the Continuum

I Reid DPhil 1971-76 M W Thompson Sputtering Processes in Gold

S D Mukherjee DPhil 1973-76 D W Palmer A Study of Proton Channelling and 

                                                                                                                                        Dechanneling in MgO

A P Webb DPhil 1973-76 P D Townsend Refractive Index Changes Produced in Silica by 

                                                                                                                                         Ion Implantation


B Cefalas MSc 1976-77 P D Townsend Temperature Effect on Refractive Index Changes 

                                                                                                                                       Formed by Ion Implantation

M Wintersgill DPhil 1974-77 P D Townsend Luminescence in LiF: Mg: Ti

R Strong DPhil 1974-77 M W Lucas Electron Loss From Light Ions

R E Kaim DPhil  !974-77 D W Palmer Oxygen Locations and Oxygen-Defect 

                                                                                                                                       Interactions in Ion Irradiated Niobium

P J Chandler DPhil 1974-77 P D Townsend Radiation Induced Fluorescence in Insulators 

        P Barker                              DPhil           1975-78                  D W Palmer                A Study of Proton- Irradiation Damage of 
                                                                                                                                                 Germanium

S Ahmad DPhil 1976-80 M W Thompson Effect of Ion Mass on the Energy Spectra of 

                                                                                                                                        Sputtered Gold Atoms

H J Whitlow DPhil 1977-80 M W Thompson Low Energy Ion Implantation of Silicon 

                                                                                                        D J O’Connor

C D Meekison DPhil 1978-81 D W Palmer rradiation Effects in Degassed and 

                                                                                                                                                  Oxygen-Doped Niobium

        A A Rezazadeh                   DPhil          1979-82                   D W Palmer                Electrical Studies of Gallium Arsenide          
                                                                                                                                                 Irradiated by Light Ions and Electrons

PW Haycock MSc 1980-81 P D Townsend Polarisation studies in lithium niobate and 

                                    									lithium tantalate

M Kijek DPhil 1980-83 D W Palmer Application of Nuclear Reaction and RBS 

                                                                                                                                     Techniques for Studies of Impurity Diffusion in
                                                                                                                                      Metallic Glasses

KI Ahmed MPhil 1981-83 P D Townsend Emission spectra during thermoluminescence

DEM Arafah DPhil 1981-84 P D Townsend Defect studies in insulators using ion beam techniques 

        KF Man			     DPhil           1981-84                  M W Lucas	         Electron loss to the continuum

AB Faik DPhil 1981-84 P D Townsend Refractive index measurements of ion exchanged 

and ion implanted waveguides

D Georgiacodis DPhil 1981-84 D W Palmer Low Temperature Ion-Irradiation Effects in Silicon 

                                                                                                                                       Studied by the Ion-Channelling Technique

P S Nandhra DPhil 1982-85 D W Palmer Electrical Characterisation of High-Dose 

                                                                                                                                        Proton-Irradiated MBE Gallium Arsenide

N S McCartney D Phil 1983-86 D W Palmer Helium-Ion Irradiation Effects in Ferritic Iron Alloys

WO Siyanbola MSc 1985-86 P D Townsend Thermoluminescence of zircons

JA Strain DPhil 1984-86 P D Townsend Angular distributions of sputtered particles

PW Haycock DPhil 1984-86 P D Townsend Ion beam induced luminescence and polarisation reversal in ferroelectric crystals

Hanafi Atan MSc 1984-86 M W Lucas Collision Induced Autoionisation of 2.0 - 2.4 MeV 

                                                                                                                                      Ar+ and O+ Ions

F Lama DPhil 1984-86 P D Townsend Sputtering processes in UO2 and UF4


C P Hobbs DPhil 1985-88 D W Palmer The Effects of Surface Topography and of Sample 

                                                                                                                                       Heterogeneity in Nuclear Microprobe  
                                                                                                                                       Ion-Beam Analysis

SE Lax DPhil 1985-87 P D Townsend Refractive index profiles produced by ion 

implantation in insulators

LH Abu-Hassan DPhil 1985-87 P D Townsend Optical studies of ion beam irradiated LiF and SiO2

Hanafi Atan DPhil 1986-89 M W Lucas Charge Changing and Multipole Expansions of Electron Loss to the Continuum 

        W O Siyanbola                    DPhil          1986-89                   D W Palmer               Production and Annealing of Proton-
                                                                                                                                                Irradiation-Induced Defects in n-GaAs

EK Glavas DPhil 1986-88 P D Townsend Ion implanted optical waveguides in lithium 

tantalate and lithium niobate

        DA Parks                            DPhil           1986-89                  P D Townsend   	         TL dating and geochemistry of brickearths in SE

England

BJ Luff DPhil 1986-89 P D Townsend Cathodoluminescence of oxides

AAS Al-GHamdi DPhil 1986-89 P D Townsend Optical studies associated with ion irradiated oxide materials

RA Wood DPhil 1987-90 P D Townsend Optical absorption studies in Al2O3 LiNbO3 

and LiF during ion implantation

P Abrahams MSc 1987-88 D W Palmer

ND Skelland MSc 1989-90 P D Townsend Silver colloids in glass L Zhang DPhil 1987-90 P D Townsend Ion implanted waveguides in electro-optic and laser materials

CA Perks DPhil 1988-91 P D Townsend Techniques for TL glow curve analysis and dose response of individual glow peaks in LiF

AC Irvine DPhil 1989-92 D W Palmer Lattice Defects in As-Grown and Irradiated 

                                                                                                                                       GaAs, AlGaAs and InGaAs

AH Khayrat MPhil 1990-92 P D Townsend TL and temperature gradient effects in microcline

MR Khanlary DPhil 1989-92 P D Townsend Luminescence of selected insulators and optical fibres

LS Babsail DPhil 1989-92 P D Townsend Formation of optical waveguides and SHG by ion 

implantation

MJ Rodman DPhil 1990-93 P D Townsend Characterization of ion implanted optical waveguides 

in selected laser crystals

N Hamelin DPhil 1990-93 P D Townsend SHG in ion implanted waveguides

M Houe MPhil 1992-94 P D Townsend Thermal domain reversal of LiNbO3 for SHG

N D Skelland DPhil 1990-94 P D Townsend High temperature ion implantation into insulators

DE Hole DPhil 1991-94 P D Townsend Optical effects of ion implantation into glass

G Kakarantzas DPhil 1991-94 P D Townsend Ion implanted waveguides in laser glasses

N Can DPhil 1991-95 P D Townsend Studies of ion implantation into insulators using 

nuclear methods, luminescence and waveguide
techniques

J R Ayres DPhil 1992-95 D W Palmer Electrically Active Defects Associated with 

                                                                                               S D Brotherton (PRL)     Dislocations and Grain Boundaries in Silicon

DRR White DPhil 1992-95 P D Townsend Spectral luminescence studies of rare earth doped CaF2 

and some synthetic minerals

S J Hartnett DPhil 1992-96 D W Palmer Uniaxial Stress / DLTS Studies on Deep Level Defects 

                                                                                                                                      in n-GaAs

AH Jazmati MSc 1994-95 P D Townsend Luminescence of pure and doped thulium barium 

fluoride

BJ Fonrobert MSc 1994-95 P D Townsend The photorefractive effect in BGO waveguides

F Lamouroux MSc 1994-95 P D Townsend Spectrometry measurements of glasses used for optical 

Waveguides

MD Bateman DPhil 1992-95 P D Townsend The chronology of coversand deposition in Britain

U Fritz MSc 1992-93 D W Palmer

SG Raymond DPhil 1993-95 P D Townsend Luminescence of BGO (2:3)

A Canimoglu DPhil 1994-97 D W Palmer Studies of Lattice Defects in As-Grown and 

                                                                                                                                      Irradiated n-InP

S Hallensleben MSc 1995-96 P D Townsend Luminescence of ion implanted Eu in sapphire and 

Er in silica

SA Holgate DPhil 1993-96 P D Townsend Luminescence studies of fluorides, glasses and ZnS

X Huang DPhil 1994-97 P D Townsend Ion implanted optical waveguides and laser ablated 

Bragg waveguide gratings

J Merbay MSc 1996-97 P D Townsend Surface analysis of float glass using 

cathodoluminescence

I Okur DPhil 1995-98 P D Townsend Waveguide and optical studies of insulators using ion implantation

AP Rowlands DPhil 1995-98 P D Townsend Thermoluminescence detection of phase transitions: 

their effects and applications


C Deibel MPhil 1997-99 P D Townsend Laser annealing of copper and silver colloids in fused 

quartz

A Burkhardt MPhil 1997-99 P D Townsend Effects of applied fields during annealing of metal 

nanoparticles

VA Smith MPhil 1997-99 P D Townsend Cathodoluminescence of silicates

M Fleischer MSc 1998-99 P D Townsend Wavelength resolved image integration for 

luminescence applications

        A K Jazmati		    DPhil	1996-99	         P D Townsend   	         Optical properties and laser induced fluorescence from
BGO:RE waveguides

NA Gallen DPhil 1995-99 P D Townsend Ion implantation waveguide formation in transition 

metal doped insulators

T Karali DPhil 1996-99 P D Townsend Luminescence of rare earth doped dosimeters

S Hallensleben DPhil 1996-99 P D Townsend Enhanced sensitivity and speed in photomultiplier 

Tubes

G Vazquez DPhil 1997-2000 P D Townsend Advances in quality of optical waveguides on 

Nd:YAG and LiNbO3

SW Harmer DPhil 1997-2000 P D Townsend Enhanced absorption photocathodes

R Brooks DPhil 1998-2001 P D Townsend Ion beam luminescence of materials

M Al-Maghrabi DPhil 1998-2001 P D Townsend Thermoluminescence spectra from sulphates, fluorides 

and garnets doped with rare earth ions

V Ramachandran DPhil 1999-2002 P D Townsend Luminescence spectra of lead tungstate, spodumene 

and topaz crystals

PJT Nunn DPhil 2000-03 P D Townsend Characterisation of potassium tantalate niobate 

waveguides formed by ion implantation and surface
studies of Nd:YAG crystals

RJ Downey DPhil 2003-06 P D Townsend Improvements in photomultiplier performance

LA Valberg DPhil 2004-07 P D Townsend Low level light detection



First Known Destinations or Employers of Graduate Students from the initial group of 1965-75

Adam Hilger Scientific Publishing AERE Harwell Bell and Howell Ltd Birmingham University British Cellophane Ltd FOM Research Institute, Amsterdam, Netherlands Hospital Physics Dept at St Luke’s Hospital Guildford Imperial College London Kent University National Radiological Protection Board National Westminster Bank Research Labs of Gillette Industries Riverina College, NSW, Australia Salford University Surrey University Sussex University UKAEA Dounreay, University of Islamabad, Pakistan Voluntary Service Overseas Warwick University York University

5 Students went to positions in industry from this Sussex MSc 10 students went on from the Sussex MSc to a Sussex DPhil and 7 to PhDs elsewhere 2 went from this Sussex DPhil to postdoctoral positions at another university


Posts held by Alumni by 2010 (where known)

Laila Abu-Hassan Professor of Physics in University of Jordan and head of department Shoaib Ahmed, Board member Pakistan Atomic Energy Agency Ahmed Al-Ghamdi Physics department, Vice Dean of Research, King Abdulaziz University Saudi Arabia Yahya Al Jammal Professor in Physics in Mosul University, Iraq Mufied Al-Maghrabi Associoate Professor Physics, Hashemite University of Jordan Dia Arafah Professor of Physics, chairman of dept, The University of Jordan Hanafi Atan Prof of Physics at The University of Sains, Malaysia Laila Babsail Ass Prof Physics, King Saud University Mark Bateman Reader in Quarternary Paleoenvironments, Dept of Geography, Sheffield University Robert Brooks Industrial electronics and optical engineer, Sussex Raymond Browning Worked in the University of York Nurdogan Can, Professor, head of physics, Science dean, and pro Vice Chancellor Celal Bayar University, Turkey Peter Chandler Director of medical software company Gordon Chapman returned to a University in Australia R Cranage Hospital physics Graham Crittenden Worked in Dounreay, now active in Scottish Butterfly conservation Ross Downey Gardening Ahmed Faik Assoc Prof Computer Science and Engineering Johnson Smith University North Carolina Stuart Harmer Lecturer Manchester Metropolitan University Nicholas Hartley European Commission (Science) Brussels Abdul Jazmati Atomic Energy Commission of Syria, Damascus, Syrian Arab Republic Alan Marwick, Consultant in computer systems in New York after retiring from senior positions with IBM A Mahjoubi returned to academia in Iran Sebastian Hallensleben Solysis, his company covers a range of scientific consulting Nicolas Hamelin The Research Cooperative, operating from Morocco Kevin Harrison Harwell after a spell at FOM, Amsterdam Peter Haycock Professor of Physics in Keele University David Hole Senior research in Engineering at Sussex University Sharon Holgate Science writer, TV and radio science presenter Xuefeng Huang Tulane University USA and Scientific computing for Ericcson in Texas Robert Kaim ATMI Connecticut USA N M Khan Owns his own company. Surface Engineering, in UK. Mohammed Khanlary Physics department Imam Khomeini International University in Iran AH Khayrat University of Birmingham Turgay Karali Associate Professor in Physics, Ege University, Turkey Francesco Lama Physics teacher in Oxford Stephen Lax Senior lecturer Communications Technology University of Leeds Bradley Luff Kotura Inc Monterey California Patricia Nunn Retired Ibrahim Okur Professor Sakarya Universitesi, Fen Edebiyat Fakultesi, Fizik Bolumu, Mithatpasa, Adapazari, Turkey Heine Pabst Deceased Chris Perks Technology manager Landauer Europe Vasuki Ramachandran Institute of Particle Science and Engineering, University of Leeds SG Raymond Post doc in New Zealand A A Rezazadeh Professor of Electronics, University of Manchester / UMIST Matthew Rodman Chemistry dept of Keele University Aled Rowlands Geography lecturer in Aberystwyth University, private consultant and TV and radio science presenter Willy Siyanbola Leader of NACETEM Obafemi Awolowo University, Ile-Ife, Nigeria. Neil Skelland Research in QinetiQ (Atlas Electronik UK) Victoria Smith Laser ranging in Herstmonceaux Julie Strain Senior engineer of Intel (deceased) R Strong Radiation Safety at Windscale Lin Zhang Professor of Electronic Engineering in Aston Leo Valberg Market risk analyst at RBS, London Gloria Vazquez Lecturer in Physics, Leon University, Mexico Robert Watkins Aerospace engineering I Physics department of Oxford University Harry Whitlow, Professor of Applied Materials, Lund University, Sweden and Jyvaskyla University, Finland. Alan P Webb Electronics industry manager in Plessey (retired) Mary Wintersgill Professor and head of physics department Annapolis Naval Academy


The preceding is only a partial list and more details, updates, and addition of data for uncited students would be welcome. We would like details for the following C Foster Z Sumengen B Stocking M Kidd D Richards T G Williams D J Elliot S Harbinson P J Mac Donald A H G El Dhaher T C Ang T F Bartley D Bean J P Davies G G W Durbin J M Gilkes S D Hartnett G W Nielsen R R Armstrong P Barlow J D Lee B T Meggitt I I Sheikh J P Summers P Barker S Datta S E Donelly D W Garlant J W Muncie R Bin Jaya M Brown A Nyaiesh P Goode I Reid S D Mukherjee B Cefalas P Barker KI Ahmed EK Glavas DA Parks RA Wood M Houe G Kakarantzas DRR White BJ Fonrobert F Lamouroux J Merbay C Deibel A Burkhardt M Fleischer NA Gallen 

          and others.
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