1. Research structure and environment
1. 1 Overview
The RAE 2008 assessment period has been the most productive and rewarding in our history. Since 2001 the research of the Department of Physics has undergone a major reorganisation, a process coupled to eight new academic appointments. Research has been increasingly focussed into four linked areas of condensed matter physics and photonics and we enter 20 full-time academic staff with a research portfolio representing strength in depth. Highlights during the assessment period include:
· Publication of over 500 papers in refereed journals, including 6 Science, 5 Nature, 7 Nature Materials/Photonics/Physics, 39 Physical Review Letters and 4 Nanoletters. Of these papers 50 have been cited more than 30 times and 10 have more than 100 citations.
· Appointments of top international quality, including Kovalev (from TU Munich), Maier (Caltech), Skryabin and Wilding (both former Royal Society of Edinburgh Fellows), Benabid (EPSRC Advanced Fellow) and Wadsworth (Royal Society URF).
· Recognition of our research through Russell’s election as an FRS, Benabid’s award of the EPS Fresnel Prize, Knight’s Leverhulme Research Fellowship, Bending’s Mott Lecture, and Walker’s Royal Society Industrial Fellowship.
· Major University investment in Physics, including over £1M for nanofabrication facilities and over £2M for optical fibre fabrication and characterisation facilities.
· A strong track record of obtaining external research funding. The submitted staff have a current grant portfolio of £8.1M, with a further £0.7M announced but not yet started.
1.2 Research areas: Research in condensed matter physics and photonics is grouped as follows:
A - Fibre photonics: linear and nonlinear photonics, particularly in the context of photonic crystal fibres. Group members: Benabid, Birks, Knight, Russell, Skryabin, Wadsworth.
B - Semiconductor photonics and plasmonics: electron-photon interactions in semiconductor and metallic systems. Group members: Andrews, Davies, Kovalev, Maier, Wolverson.
C - Nanoscience: structural, transport, magnetic, superconducting properties of condensed matter at the nanoscale. Group members: Bending, Coleman, Gordeev, Ilie, Nogaret, Salmon.
D - Condensed matter theory: research across the condensed matter / photonics spectrum, but focussing on the atomic and electronic properties of matter. Group members: Bird, Crampin, James (submitted to UoA 14), Walker, Wilding.
During the assessment period, there has been a restructuring of those areas of research which lie outside these core themes of the department. Although we retain an interest in remote sensing, this research is now carried out within the University Research Centre for Space, Atmospheric and Oceanic Science (CSAOS). Members of CSAOS (including Blondel and Pace from Physics) have been submitted to UoA 24. With Humphrey’s departure, the only ongoing research in Medical Physics is Cronin’s work on microwave devices. Cronin has also been submitted to UoA 24.
1.3 Staffing policy: The recruitment of new academic staff during the assessment period has substantially strengthened the department, replacing less research active staff with top flight researchers. The new appointments are: Benabid, Skryabin and Wadsworth in fibre photonics (Benabid and Wadsworth take up academic posts at the end of their fellowships); Kovalev and Maier in semiconductor photonics and plasmonics; Gordeev and Ilie in nanoscience; and Wilding in condensed matter theory.
Benabid, Ilie, Maier, Skryabin, Wadsworth and Wilding all joined the department as probationers. New academic staff have light teaching loads for two years to accelerate and consolidate their research activities and we give priority to probationers in allocating University and DTA research studentships. In addition to departmental mentoring, the University’s staff development unit offers a range of courses to support early career researchers, including preparing proposals, project management, consultancy and commercialisation of research.
The department has also recruited 2.6 FTEs of new non-research academic staff since 2001. This has had the effect of reducing the average teaching and administration load of the submitted staff, thus allowing more time for research.
1.4 Infrastructure investment: The University’s continued strong commitment to the physical sciences is shown by the major investment of SRIF funds into both Physics and Chemistry. In Physics, over £1M has been invested in a new nanofabrication facility, and over £2M has been invested in new facilities for fibre fabrication and photonics research. There has also been a substantial refurbishment of the nanoscience laboratories, and new provision for Kovalev. These investments have provided the core research groups with world class facilities, and have contributed to a research environment which attracts the best academics, research staff and PhD students.
1.5 Research funding: The department places considerable emphasis on supporting academics in applying for funding. The Research Committee and a dedicated funding “gatekeeper” identify possible funding opportunities and help people applying to a particular funding body for the first time. A rigorous internal refereeing of applications has been initiated with the aim of ensuring that the scientific case is presented as strongly as possible. The success of these measures can be seen in the fact that 16 of the 20 academic staff in this UoA are principal investigators on current grants and contracts (Benabid £943k, Bending £840k, Bird £201k, Birks £859k, Coleman £63k, Davies £281k, Gordeev £110k, Knight £806k, Kovalev £334k, Maier £325k, Nogaret £564k, Salmon £306k, Skryabin £155k, Wadsworth £907k, Walker £335k, Wolverson £725k). The great majority of this funding (and of grant income throughout the assessment period) has been obtained through the highly competitive responsive mode mechanism.
The nanofabrication and fibre fabrication facilities underpin much of the experimental research in the department. Both have been set up as University facilities in the full economic costing (FEC) framework, and academics have been successful in obtaining external funding to support the running costs and depreciation costs of the facilities. This provides ring-fenced funding to sustain and develop these key facilities in the medium-term.
1.6 Research staff, PhD students and visitors: Policies for the support of research staff and PhD students are set by the University Research Committee (of which Knight is a member). The University has appointed a Career Development Advisor for research staff, and the Research Staff Working Group ensures that best practice is disseminated in support of researchers. Bending is a member of this group; he is also the departmental Research Staff Coordinator, acting as the first point of support and information for our research staff.
Support for PhD students is provided through the graduate office, the international office and the postgraduate student association, coordinated by the University’s Director of Postgraduate Research Development. Departmental support is coordinated by the postgraduate Director of Studies, who oversees the appointment of supervisors, transfer of registration from MPhil to PhD, annual monitoring reports, etc. The Director of Studies also oversees skills training for PhD students, in collaboration with University and Faculty coordinators. A recent example of skills training was a 3-day event held by the department at Gregynog in 2006, when 33 of our PhD students attended presentations on networking, communication skills, publishing and presenting, ethics in research, the student-supervisor relationship and thesis writing.
The research groups provide a supportive environment for research staff and PhD students. Regular seminars and topical meetings provide forums for presentation of their work and for learning about the wider context of their research. All researchers present their work at national and international conferences and schools; funds are provided by the department to assist PhD students to participate. There is also an annual cross-disciplinary conference, organised by and for the University’s research student community.
The department strongly encourages visitors to add to the research environment. During the assessment period, 33 visitors have stayed for over 1 month; examples include Professor Kochereshko (Ioffe Institute, 2 months), Dr Taru (Senior Engineer, Sumitomo Corporation, 18 months), Professor Usuki (Yamagata University, 1 year), Professor Vladimirov (WIAS, Berlin, 3 months).
1.7 Research strategy: The key elements of the department’s research strategy are:
· To focus on a small number of closely related fields, in order to exceed the critical mass necessary for internationally leading research;
· To work in condensed matter physics and photonics: areas that provide outstanding opportunities for cutting-edge, fundamental research, and where ground-breaking applications are likely to emerge;
· To develop research groups that provide a framework for collaboration between academics and which support research staff and PhD students in their scientific and career development;
· To invest in these groups through excellent academic appointments and the provision of state of the art facilities;
· To support each academic as a leader of research: in building their own research team and obtaining funding for their work;
· To respond rapidly and flexibly to take advantage of new research directions and collaborations in areas where the department is poised to make a major international impact.
1.8 Forward look: To maintain the future vitality and quality of our research we will build on this strategy by:
· Continued sustainable expansion of the department, based on our ongoing strong undergraduate recruitment. Additional appointments will further strengthen the core research areas and foster interdisciplinary links at the University, national and international level.
· Bringing more of the department’s research into University Research Centres, a structure that encourages interdisciplinary collaborations and provides a clear identity that helps to attract both internal and external funding. We have already formed the Centre for Photonics & Photonic Materials and the Centre for Space, Atmospheric and Oceanic Science. In 2008 a Nanoscience Research Centre will be created, jointly with colleagues in Chemistry.
· Building on the success of the Nanofabrication and Fibre Fabrication facilities by developing new University research facilities sustainable under FEC funding. A high performance computing cluster (operational in early 2008) is currently being developed with colleagues in Chemistry, Computer Science and Mechanical Engineering.
· Increasing the number of PhD students. The growth in the department’s grant portfolio over the last two years has increased both the number of project studentships and the size of the department’s DTA. 16 new PhD students started in Autumn 2007 – the department will concentrate efforts on increasing recruitment further in the future.
· Encouraging leadership of and participation in national and international collaborations and networks, and developing research collaborations that make a major contribution to the regional economy through the South West RDA and Great Western Research.
The scientific objectives of the research groups are outlined below.
2. Fibre photonics
2.1 Overview: This group has an outstanding international reputation for its work on the optics of microstructured materials, in particular, the photonic crystal fibre (PCF), jointly pioneered by Birks, Knight and Russell. With the addition during the assessment period of Benabid, Skryabin and Wadsworth, the group continues to lead major international advances in this field. They have strong interactions with Bird and Maier, and with them formed the Centre for Photonics & Photonic Materials (CPPM) in 2005.
Highlights during the assessment period include:
· Demonstration of a world-record hollow-core fibre, in which light is trapped in a single optical mode in a 10 micron air hole by a photonic bandgap cladding, for many kilometres length;
· Development and comprehensive physical understanding of novel optical fibres, including the first all-solid photonic bandgap fibres, broad band hollow-core fibres and fibres for nonlinear applications;
· Using the nonlinear response of new types of fibre to deliver and transform laser light, for example in supercontinuum generation (a spectrally broad, high-brightness light source generated by a near-single frequency), photon pair generation for quantum communications, and ultrashort pulse compression and delivery using solitons;
· Revolutionising gas-light interactions through the use of hollow-core fibre as a gas cell;
· Publication of 182 refereed journal articles, including 3 Nature, 1 Nature Physics, 2 Nature Photonics, 5 Science and 11 Physical Review Letters. These 182 papers have nearly 3500 citations and their H-index is a remarkable 32.
The group is extremely well equipped. Their world-class fibre fabrication and laser facilities (funded in part by a £1.7M JIF award) were re-located into a new purpose-designed building in 2005 (SRIF, £2M). The group currently has 7 PDRAs and 11 PhD students; the research environment is strengthened by weekly group meetings and topical meetings, and by a regular flow of international visitors (there are currently 5 long-term visitors). There are collaborations and links with over 50 research groups around the world who highly value fibre samples and expertise from Bath. Examples include: Max Planck Institute for Quantum Optics, Garching (Haensch’s collaboration with Bath was cited in his Nobel Prize speech); Los Alamos National Laboratory (Taylor); Anglo-Australian Observatory (Bland-Hawthorn); Texas A&M University (Sokolov).
In 2001, Birks, Knight and Russell founded a spin-out company, BlazePhotonics, to commercialise their invention of PCF. This received $9M of start-up funding and was sold in 2004. It developed a huge amount of technical expertise in fibre design and fabrication which has fed back into the academic group. There are currently funded collaborations with several UK-based and European companies (Fianium, Alcatel-Lucent, Draka-Comteq, Osyris, Heraeus) and the group is developing a new patent portfolio following the BlazePhotonics sale.
In September 2005, Russell became leader of a Max Planck Research Group at the University of Erlangen. He has retained a 20% appointment at Bath which facilitates joint research projects such as a project on biomedical applications of PCF, funded by Russell’s Koerber Prize. The group has remained highly productive through the transition, and the appointments (in October 2005) of Benabid and Wadsworth to permanent positions at the end of their fellowships have secured its long-term future. The current grant portfolio is £4.05M (£2.65M of this obtained since Russell took up his post in Germany); a further £0.56M has been announced but not yet started.
Benabid leads research on gas-laser interactions (including stimulated Raman scattering and electromagnetically induced transparency) in hollow-core fibres. The work is enabling new possibilities in coherent and quantum optics, including the development of novel optical waveform synthesisers and atomic clocks.
Birks leads research on the linear properties of optical fibres, including the analysis of guidance and loss mechanisms and the processing of fibres to create structures for novel optical devices. He is working to develop applications based on non-uniform fibres and aerogels, exploiting the extra degrees of freedom afforded by the complexity and variety of PCF structures.
Knight is Director of the CPPM and leads research on the design and fabrication of fibres, alongside characterisation and control of their linear and nonlinear optical properties. His long-term objective is to be able to engineer the optical properties of fibre-guided modes to influence their nonlinear response, in order to generate, manipulate and deliver powerful laser beams.
Skryabin uses analytical and numerical modelling to identify and initiate new research directions in nonlinear guided-wave optics. He aims to find realisable manifestations (in, for example, optical fibres, resonant gases or optical resonators) of general and fundamental phenomena to advance the understanding and applications of soliton physics.
Wadsworth leads research on generating light in new ways, with applications from metrology and quantum information to bioimaging and sensing. He is developing supercontinuum sources for new wavelength ranges, investigating correlated multiple photon generation and developing PCFs to complement a new generation of fibre lasers which are just becoming commercially available.
2.2 Evidence of esteem
Invited talks: 121 invited talks at international conferences (Benabid 13, Birks 17, Knight 31, Russell 40, Skryabin 9, Wadsworth 11). Highlights include: Benabid, Photonics West 2005, 2006, CLEO 2003; Birks, CLEO 2002, 2005, 2007 (tutorial), OFC 2004, 2006; Knight, IEEE Topical Meeting 2003 (plenary), ECOC 2005 (tutorial); Russell, LEOS 2002 (Plenary), CLEO-Pacific Rim 2003 (Plenary), PECS-VII (Plenary); Skryabin, Nonlinear Guided Waves 2002, ICONO 2005, 2007; Wadsworth, CLEO 2001, 2003, OECC 2003 (tutorial).
Invited papers: Reviews of PCF: Knight (Nature, 2003, 169 citations); Russell (Science, 2003, 418 citations).
Conference organisation: Organised / organising committee of 21 international conferences, including: Birks, ECOC (Committee Member 2005 to 2007); Knight, ECOC (workshop Chair and Organiser, 2006), Nonlinear Photonics (Programme Chair, 2007); Russell, POWAG 2004 (Chair); Skryabin, EOS (Committee Member, 2006), Nonlinear Effects in Photonic Materials (Organiser, 2007); Wadsworth, CLEO Europe (Committee Member 2005, 2007)
Prizes and awards: Benabid: EPSRC Advanced Research Fellowship (2003-date); Fresnel Prize of the European Physical Society (2005) for outstanding contributions to quantum electronics and optics. Knight: Leverhulme Research Fellowship (2005-06). Russell: Fellow of the Royal Society (2005); Royal Society/Wolfson Research Merit Award (2005); Koerber Prize for European Science (2005); Thomas Young Prize (2005) and Applied Optics Division Prize (2002) of the IoP; Distinguished Lecturer Award (IEEE Lasers & Electro-Optics Society, 2004-06). Wadsworth: Royal Society University Research Fellowship (2001-date).
Editorial work: Birks: Optics Communications (Editorial Board, since 2003). Skryabin: Optics Express (Associate Editor, since 2006).
Consultancy/Advisory work: Benabid: consultant for Teraxion, Toptica Photonics and Triad Technology. Birks: consultant for Lightwave Electronics and Anglo-Australian Observatory. Knight: consultant for Fianium, Crystal Fibre, NPL, NRLM (Japan). Wadsworth: Royal Society summer studentships (Panel Chair); Reviewer and Assessor for Paul Instrument Fund.
3. Semiconductor photonics and plasmonics
3.1 Overview: This group has expanded since 2001, with appointments of Kovalev (2005, bringing £1M of equipment from the Technical University, Munich) and Maier (2004, from Caltech). Key research areas are: generation and detection of THz radiation (Andrews); nanoporous silicon and silicon nanoparticles (Kovalev); magneto-optical behaviour of semiconductor heterostructures (Davies, Wolverson); plasmonics (Maier). Since 2001, the group has published 111 refereed journal articles, including 9 Physical Review Letters, and 3 Nature Materials/Photonics/Physics.
The group’s current grant portfolio is £1.67M and its four expanding spectroscopy laboratories are world class. It has strong links with the fibre-photonics and nanoscience groups and makes considerable use of their infrastructure. Notable international collaborators include the Ioffe Institute (St Petersburg), Institute for Materials Research (Japan), CNRS/LPN (Paris), and the Universities of Madrid, Zaragoza, Leuven, Kobe and Moscow.
Andrews’ research has two themes. First, dynamical processes in semiconductors excited by femtosecond optical pulses are studied via time-resolved, coherent THz emission. Highlights include identification of emission mechanisms and new insights into the creation and stability of coherent excitations. Second, THz devices are developed for spectroscopy, imaging and sensing, with improved dynamic range and bandwidth. Currently, with Maier, he is developing novel THz waveguides using highly confined “spoof” plasmons on metamaterial surfaces.
Davies uses magneto-optical techniques to study charge carriers and excitons under quantum confinement in semiconductor heterostructures to identify mechanisms that control light-emitting efficiency and spintronic behaviour. A highlight is his discovery of remarkable universal behaviour in which the structure of excitons changes as they move. With Wolverson, he has developed world-leading equipment for spin-flip Raman scattering and optically-detected magnetic resonance; they have also invented (with Bingham, PDRA) an ultra-sensitive, high-resolution coherent-Raman magnetic resonance technique for future studies of spintronic materials.
Kovalev creates and investigates Si-based nanometric materials with entirely new physical properties and, therefore, new functionality in photochemistry, biology and medicine. Highlights include: spin-flip activation of oxygen molecules (with the discovery that photosynthesis, energy transfer and photochemical reactions can be mediated by silicon nanocrystals); development of photonic devices based on nano-Si; and light emission from these systems. A further highlight has been his creation of nanosilicon-based explosives, followed by their development as vehicle airbag initiators.
Maier’s research has been a leading stimulus to the emerging field of plasmonics, an area of nanophotonics concerned with fundamentals and applications of surface plasmon excitations. Highlights include: demonstrating the potential of plasmon waveguides as the basis of a nanoscale photonics infrastructure; demonstration of metal nanoparticle plasmon optical waveguides (including novel coupling schemes via conventional optical fibres); and a new metamaterials approach extending concepts for visible frequencies to the far-infrared.
Wolverson investigates the spin and magnetic effects of magnetic ions incorporated into semiconductor heterostructures. Intense worldwide activity in spintronics has stimulated exploration of these new systems and Wolverson studies them with several spectroscopic techniques, including spin-flip Raman scattering, optically-detected magnetic resonance, vibrational and coherent Raman spectroscopies and X-ray magnetic circular dichroism (ESRF). The work has attracted recent BBSRC/EPSRC funding (£724k), with Bingham and Davies, for the development of spectroscopic ESR imaging.
3.2 Evidence of esteem
Invited talks: 41 invited talks at international and 5 at national conferences (Andrews 5, Davies 8, Kovalev 16, Maier 15, Wolverson 2), together with 40 invited colloquia, 16 in the UK and 24 overseas. Highlights include: Andrews, International THz Workshop, 2001, International School in Solid State Physics, 2005; Davies, International Workshop on II-VI Heterostructures, 2002, International Winter School in Semiconductor Physics, 2007; Kovalev, MRS Spring Meeting 2003, MRS Fall Meeting 2004, EMRS Conference 2006; Maier, MRS Spring Meeting 2004 (tutorial), PIERS 2007, Surface Plasmon Photonics, 2007; Wolverson, International Workshop on II-VI Semiconductors, 2005.
Conference organisation: Organised / organising committee of 10 international conferences, including: Davies, International Conferences on II-VI Compounds (Programme/Advisory Committees, 2001/03/05/07); Kovalev, Porous Semiconductors Science & Technology (Committee, 2006); Maier, MRS Fall Meeting 2005 (Plasmonics Symposium Organiser), EMRS Spring Meetings 2007 (Conference Organiser) and 2008 (Functional Plasmonics Symposium Organiser); Wolverson, 12th, 13th International Conferences on II-VI compounds (Programme Committees).
Editorial work: Davies: Japanese Journal of Applied Physics (Overseas Editor, since 2005). Maier: Journal of Biomedical Nanotechnology (Editorial Board, since 2005); Advances in Optoelectronics (Guest Editor, 2006); CRC Handbook on Metamaterials (Editorial Board, 2007 onwards).
Consultancy/Advisory work: Andrews: Consultant for Teraview and Toshiba. Davies: ISIS Muon Beam Access Panel member (7, one as Chair); CCLRC Review Panel to advise on UK Muon Beam Facilities. Kovalev: Collaboration with TRW Automotive (nanosilicon-based initiators for air bags).
Leadership of research collaborations: Kovalev:FP6 Project Coordinator, 2005 to date. Wolverson: FP6 INTAS Network Coordinator, 2002-05.
4.1 Overview: Experimental research in the group focuses on investigating and manipulating the properties of materials at the nanoscale as well as combining elements from different functionality groups (e.g. electronic, photonic, magnetic, etc.) to realise systems with entirely new physical properties; research thus covers both fundamental and applied aspects of nanoscience. Key themes are: vortex phases in superconductors (Bending), spintronics (Bending, Gordeev, Nogaret), electrical and mechanical properties of nanostructures and hybrid nano-materials (Bending, Gordeev, Nogaret, Ilie), neutron scattering studies of glasses and liquids (Salmon), and positron studies of defects (Coleman). The work is becoming increasingly interdisciplinary and close collaborations exist with several Physics, Chemistry and Chemical Engineering departments worldwide (e.g., NIMS (Japan), University of Tokyo, Argonne National Laboratory, McMaster University, University of Antwerp, CNRS-Paris, EPFL (Switzerland), Moscow State University). Ilie’s appointment is linked with a related post in Chemistry which further strengthens the group’s research in hybrid nanomaterials. Future research will target next-generation electronic and data storage devices as well as applications for nanotechnology in biology and medicine. During the assessment period, group members have published 150 refereed journal articles, including 2 Nature, 2 Nature Materials, 1 Science, 2 Nano Letters and 12 Physical Review Letters.
Our facilities have been further enhanced since 2001 by construction of a new nanofabrication laboratory, supported by a Royal Society-Wolfson grant and £1M of SRIF money. This is central to many of the group’s research activities. Salmon and Nogaret also make extensive use of international neutron and X-ray facilities and the High Magnetic Field Laboratory (Grenoble). Coleman’s laboratory houses unique positron beam systems for characterisation of near-surface and interface defects. The group currently has 5 PDRAs, 2 visitors (including a Marie Curie Fellow) and 13 PhD students; the lively research environment is further enhanced by weekly group seminars involving collaborators from several Departments. The current grant portfolio is £1.82M, with a further £0.15M announced but not yet started.
Bending’s research focuses on the magnetic properties of nanoscale Superconducting, Ferromagnetic and hybrid S/F materials. Highlights include the discovery of a new state consisting of chains of vortices in layered superconductors under tilted magnetic fields. This was exploited in a unique generic approach to nanoparticle manipulation in binary systems of interacting particles. Current research focuses on hybrid S/F structures to realise high critical current superconductors and novel “fluxtronic” devices as well as artificial ferromagnetic domain structures for applications in current-switched spintronic devices.
Coleman’s research involves positron beam spectroscopy of near-surface atomic-scale structures. He has recently resolved many open scientific and technological questions including the identification of fluorine-vacancy complexes responsible for the elimination of dopant diffusion in Si and the influence of defects on the electronic performance of thin films and Si optical waveguides. A highlight is the first measurement of the migration energies for silicon interstitials and monovacancies in ion-implanted silicon. The recent development of a spin-polarised positron beam will lead to work on magnetic semiconductor films and nanoparticles.
Gordeev’s research has two distinct themes: magnetic superlattices, and novel applications of nanotechnology. In the former, an entirely new type of “exchange spring” magnetic superlattice was developed exhibiting negative coercivity with potential applications in magnetoresistive sensors. In the latter, he is exploring a new generation of charge transport devices based on electron “shuttling” in nanostructures as well as developing novel methods for tracking proteins in living biological cells using magnetic labelling. This interdisciplinary research is carried out in collaboration with groups in Chemistry and Chemical Engineering in Bath.
Ilie’s research centres on hybrid nano-materials and their applications. This includes systems of inorganic nanowires encapsulated inside nanotubes; new functionalities arising from spatial confinement of the nanowire will lead to applications in nano-electronics, spintronics and electrochemistry. A highlight is the demonstration of a new technique which allows the integration of individual biological or molecular nanostructures (previously considered too fragile) into devices for the first time. New collaborations with Bath Chemistry will couple nanotubes with molecular systems to develop spatially-controlled nanotube-molecular architectures.
Nogaret’s research has two themes: low dimensional electron systems confined by microscopically inhomogeneous magnetic fields, and micro-machined transmission lines that propagate electrical impulses and mimic biological nerve fibres. He has shown that spin resonance can be excited by injecting an electrical current through a magnetic field gradient and is seeking to detect its fluorescence emission to develop nanoscale wireless transceivers. He has also demonstrated the feasibility of propagating electrical impulses through non-linear semiconductor wires and is developing artificial “nerve fibres” and neuron-like devices for applications in neural networks.
Salmon’s research focuses on investigations of the atomic scale structure and dynamics of liquids and glasses using neutron and x-ray scattering. Highlights include the discovery of 5-fold coordination in the first solvation shell of the Cu(II) aqua ion and the demonstration of pair correlations in network glasses that extend to unexpectedly large length scales. The long term aim of this work is to understand and manipulate the intermediate range order in these systems at the atomic level to gain insight into processes associated with the glass transition, and to develop materials with new functional properties.
4.2 Evidence of esteem
Invited talks: 41 invited talks at international conferences and 15 at national conferences (Bending 18, Coleman 9, Ilie 8, Nogaret 5, Salmon 16). Highlights include: Bending, Gordon Conference on Superconductivity, 2001, NATO Advanced Workshop on Magneto-Optical Imaging, 2003, International Symposium on Vortex Matter in Nano-Superconductors (keynote, 2005); Coleman, 13th, 14th International Conferences on Positron Annihilation; Ilie, Gordon Conference on Nanostructure Fabrication, 2002, International Conference on Intelligent Materials and Systems, 2005; Nogaret, International Conference on Semiconductors in High Magnetic Fields, 2002, DTI Spintronex conference, 2007; Salmon, 9th, 10th International Conferences on Non-Crystalline Materials (plenaries, 2004/06), 12th International Conference on Liquid and Amorphous Metals (keynote, 2004).
Conference organisation: Organised / organising committee of 18 conferences and schools, including: Bending, CMMP’03 (Symposium organiser); Coleman, 13th International Conference on Positron Annihilation (Chair of Programme Committee, 2003), 9th, 10th & 11th International Workshops on Positron Beams for Solids & Surfaces (2001/05/07); Salmon, EPSRC/IoP Winter School on Liquids and Complex Fluids (Organiser, 2007), 7th EPS Liquid Matter Conference (Programme Committee).
Prizes and awards: Bending: Mott Prize Lecture of the Institute of Physics, 2002. Ilie: Japan Science & Technology Agency Fellowship, 2005-06.
Editorial work: Bending: Superconductor Science & Technology (Advisory Board, 2005-06); Physica E (Advisory Editor, 2001-07). Coleman: Applied Surface Science (Co-Editor, 2006); J.Phys.CM (Editorial Committee, 2003). Salmon: Journal of Non-Crystalline Solids, J.Phys.CM (Guest Editor of special issues).
Consultancy/Advisory work: Bending: EPSRC Materials Programme Strategic Advisory Team member (2005-date); EPSRC Materials Programme Review Panel member (2005); UK Steering Committee Member for ESF VORTEX and NES Networks. Coleman: Scientific Consulting Board for European Intense Positron Beam Facility (2004-date). Salmon: Scheduling panel for ISIS neutron source (2002-04); Founder member of Society of Glass Technology structure group; Secretary & Treasurer of IoP Liquids & Complex Fluids group (2001-07).
5. Condensed matter theory
5.1 Overview: The group conducts research across a broad range of topics in condensed matter physics. Principal areas are: electronic properties of surfaces (Bird, Crampin), photonic crystals (Bird), nanomagnetism (Crampin), network theory applied to animal behaviour (James, submitted to UoA14), transport in electronic devices (Walker), complex fluids (Wilding). Bird and Crampin have strong links with the fibre photonics and nanoscience groups respectively, and Walker collaborates closely with experimentalists in Bath’s Chemistry department. Since 2001, the four group members submitted to UoA19 have published 97 refereed journal articles, including 2 Nano Letters and 9 Physical Review Letters.
All group members enjoy national and international collaborations with leading academics. This provides a vigorous research environment, with a regular influx of visitors and external seminar speakers. In a lively group seminar series, PhD students, postdocs and academics (both from CMT and photonics) present talks on their own research and topics of general interest drawn from articles in leading journals. The group is well resourced with local workstation clusters (funded in part by a £540k JREI award), and access to national supercomputers. The current grant portfolio totals £0.54M.
Bird’s research has two distinct themes: molecular adsorption on metallic surfaces, and light propagation in photonic crystal fibres (in collaboration with the fibre photonics group). One highlight is his development of time-dependent methods to analyse the electronic excitations that accompany adsorption on metal surfaces. This has benefited both the fundamental understanding of quantum processes at surfaces, and the interpretation of experimental results. It is having an important role in informing ongoing international research on energy dissipation at surfaces.
Crampin's research focuses on electronic structure and dynamics. A highlight is his international collaboration with experimentalists to develop the scanning tunnelling microscope (STM) as a quantitative tool for the spectroscopy of electronic surface excitations e.g. proposing the use of nanoscale resonators for this purpose. He was the first to quantify the perturbing influence of the electric field of the STM tip, thereby reconciling contradictory measurements of excitation lifetimes. This work aims to understand the fundamental physics that affects surface photochemistry.
Walker studies charge and energy transport in optoelectronic devices such as LEDs and solar cells, in close collaboration with experimentalists. She has developed novel multiscale methods for her work on organic devices, which harness modelling techniques from quantum chemistry, semiconductor and polymer physics. A highlight has been to link the performance of organic photovoltaic cells to the chemical structure and degree of phase separation of the polymer blend. Progress in this technologically important field will lead to cheaper solar power and cheap, efficient lighting.
Wilding studies bulk and surface phase behaviour of complex fluids such as colloidal dispersions. A key strand is the development of algorithms to bridge the many decades separating simulation timescales and those of phase changes. He recently introduced a Monte Carlo method which facilitates efficient study of phase behaviour for highly size asymmetric fluid mixtures − a model for colloid-nanoparticle mixtures. This advance is furthering the fundamental study of such commercially relevant materials.
5.2 Evidence of esteem
Invited talks: 21 invited talks at international conferences and 9 at national conferences (Bird 6, Crampin 2, Walker 5, Wilding 17), together with 36 invited colloquia, 23 in the UK and 13 overseas. Highlights include: Bird, Gordon Conference on Dynamics at Surfaces, 2001, Vibrations at Surfaces, 2007; Crampin, Royal Society Discussion Meeting, 2003; Walker, International School of Liquid Crystals, 2005, EU-China Workshop on Nanomaterials, 2006; Wilding, 6th EPS Liquid Matter Conference (keynote, 2005), International School in Solid State Physics, 2005.
Conference organisation: Organised /organising committee of 12 conferences and 2 summer schools, including: Crampin, Physics by the Lake Summer School (Organiser, twice), CMMP’06 (Programme Committee); Walker, Photovoltaic Science PVSAT-4 (Organiser); Wilding, CECAM workshops (Organiser, 2004 and 2007).
Prizes and awards: Walker: Royal Society Industry Fellowship (2003-06).
Editorial work: Bird: Reports on Progress in Physics (Editorial Board, 2001). Crampin: Journal of Physics: Condensed Matter (Editorial and Interface Science boards, 2003-06), Computer Physics Communications (Specialist Editor, 1997-date); Wilding: Journal of Statistical Mechanics (Editorial Board, 2007 onwards).
Consultancy/Advisory work: Bird: EPSRC prioritisation panels (3, once as Chair); EPSRC representative on Management Board for procurement of HPC(x) national supercomputer. Crampin: IoP Condensed Matter Division and Nanoscale Physics & Technology Group (committee member); IoP Theory of Condensed Matter Group (secretary); EPSRC Advanced Fellowship Panel. Walker: EPSRC prioritisation panels (7, twice as Chair); IoP Semiconductor Physics Group (secretary). Wilding: EPSRC, Panel Chair for Fellowships in Theoretical Physics.
Leadership of research collaborations: Bird: Chair of UKCP high-performance computing consortium, 2001-02. Crampin: Chair of CCP3, 2007 onwards. Walker: Coordinator of FP6 project MODECOM (13 groups, from EU, China, US, 2006 onwards).