Dr Annika Lohstroh
Biography
Annika Lohstroh grew up in central Germany, where she studied for her undergraduate Diploma in Physics at Göttingen University. She developed an interest in nuclear solid state physics during a month exchange programme with the Catholic University Louvain (Belgium). Subsequently, she continued to study this rea of physics that uses techniques originating in nuclear physics to investigate semiconductor properties, like hyperfine interaction methods and ion beam analysis. She moved to Guildford during Summer 2002 and obtained her PhD at the University of Surrey, researching charge transport properties in wide band gap semiconductors for radiation detection applications, with a particular emphasis on chemical vapour deposited diamond. She extended these studies as a Research Fellow at the University of Surrey during the following years and was appointed as Lecturer in 2008, promoted to Senior Lecturer in 2013. Her scientific aim is to understand the limitations of current radiation detector performance and to find ways to overcome these limits for a variety of applications.
Areas of specialism
Radiation Physics;
Material Analysis;
Radiation Detection Instrumentation;
Optical and Electrical Characterisation of Materials
University roles and responsibilities
- MSc Physics Programme Lead
- Radiation and Medical Physics (RAM) Group Lead
- Member of the Faculty Equality & Diversity Committee
- Module Lead PHYM041 - Experimental Group Project
- Module Lead PHY1036 - Oscillations and Waves
Previous roles
Research
Research interests
Research and development of sensors for ionising radiation, in particular
- The effect of bulk and surface defects on sensor performance in solid state detectors (including radiation damage)
- Development of pulse shape analysis for research and applications
- Novel materials to exploit optical readout (scintillors, thermoluminescence, radiation induced changes in optical properties)
Current investigation include
- Development of single crystal diamond X-ray dosimeters
- Wide band gap semiconductors for spectroscopic particle detection at elevated temperatures
- Detecting ionising radiation using polarised light
- Wide band gap materials for high energy X-ray detection
- Silica materials for dosimetry
The work is carried out collaboratively with a number of industrial partners, often supported by joint supervision of research students. Examples are the Rutherford Appleton Laboratory, the International Atomic Energy Agency, Culham Centre for Fusion Energy as well as industrial Partners.
Courses I teach on
Supervision
Postgraduate research supervision
Current doctoral students:
- Katie Ley, working on the application of silica beads for radiation dosimetry.
- Robert Smith, working on the development of a tritium monitor.
- Michael Hubbard, working on pulse shape discrimination for neutron detection.
Postgraduate research supervision
Doctoral students that have completed their theses:
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King, David John Stephen (2017): A biomechanical model for lung fibrosis in proton beam therapy. Doctoral thesis, University of Surrey.
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Hodgson, Michael (2016) Silicon carbide and diamond neutron detectors for active interrogation security applications. Doctoral thesis, University of Surrey.
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Alamoudi, Dalal (2016) Dose enhancement near metal interfaces in synthetic diamond based x-ray dosimeters. Doctoral thesis, University of Surrey.
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Astromskas, Vytautas (2016) Spectroscopic imaging using Ge and CdTe based detector systems for hard x-ray applications.Doctoral thesis, University of Surrey.
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Richards, S. (2016) Laser micromachining of cadmium tungstate scintillator for high energy x-ray imaging. Doctoral thesis, University of Surrey.
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Abubakar, Y.M. (2016) Silicon and silicon carbide radiation detectors for alpha and neutron detection at elevated temperatures.Doctoral thesis, University of Surrey.
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Boothman, Victoria H. (2016) CZT ring-drift detectors for hard x-ray spectroscopy : an investigation of design by experiment and modelling. Doctoral thesis, University of Surrey.
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Abilama, Marc (2015) Investigating the performance characteristics of bromine quenched Geiger-Müller detectors with age and temperature. Doctoral thesis, University of Surrey.
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Alruhaili, A. (2014) Development of CdTe/CZT drift ring detectors for x and γ ray spectroscopy. Doctoral thesis, University of Surrey.
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Allwork, C. (2013) X-ray beam studies of charge sharing in small pixel, spectroscopic, CdZnTe detectors. Doctoral thesis, University of Surrey.
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Kitou, D.,(2013) Experimental and simulation study of charge sharing in pixelated CdZnTe radiation detectors using the PIXIE ASIC. Doctoral thesis, University of Surrey.
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Gkoumas, S.(2012) Charge transport and radiation induced defects in single-crystal CVDdiamond. Doctoral thesis, University of Surrey.
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Rees, V. P. (2012) Evaluation of a novel neutron detector using experimental and Monte Carlo Techniques. Doctoral thesis, University of Surrey.
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Avella, P. (2012) Characterisation of silicon photomultipliers coupled to inorganic scintillating crystals for timing applications. Doctoral thesis, University of Surrey.
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Albarakaty, H. (2011) Fabrication and characterization of graphite electrodes for diamond x-ray dosimeters. Doctoral thesis, University of Surrey.
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Abdel-Rahman, M. (2011) The influence of electrode fabrication on induced X-ray photocurrents in CVD diamond radiation detectors. Doctoral thesis, University of Surrey.
My publications
Publications
Alamoudi, D., A. Lohstroh, and H. Albarakaty, The effect of dose enhancement near metal interfaces on synthetic diamond based X-ray dosimeters. Radiation Physics and Chemistry, 2017. 140: p. 25-33.
Hodgson, M., et al., Characterization of silicon carbide and diamond detectors for neutron applications. Measurement Science and Technology, 2017. 28(10).
Hodgson, M., A. Lohstroh, and P. Sellin, Alpha radiation induced space charge stability effects in semi-insulating silicon carbide semiconductors compared to diamond. Diamond and Related Materials, 2017. 78: p. 49-57.
Hodgson, M., et al., Neutron detection performance of silicon carbide and diamond detectors with incomplete charge collection properties. Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2017. 847: p. 1-9.
Richards, S., et al., Femtosecond laser ablation of cadmium tungstate for scintillator arrays. Optics and Lasers in Engineering, 2016. 83: p. 116-125.
Astromskas, V., et al., Evaluation of Polarization Effects of e(-) Collection Schottky CdTe Medipix3RX Hybrid Pixel Detector. Ieee Transactions on Nuclear Science, 2016. 63(1): p. 252-258.
Boothman, V., et al., Charge transport optimization in CZT ring-drift detectors. Journal of Physics D-Applied Physics, 2015. 48(48).
Abubakar, Y.M., A. Lohstroh, and P.J. Sellin, Stability of Silicon Carbide Particle Detector Performance at Elevated Temperatures. Ieee Transactions on Nuclear Science, 2015. 62(5): p. 2360-2366.
Abilama, M., M. Bates, and A. Lohstroh, Investigating the lifetime of bromine-quenched GM Counters with temperature. Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2015. 795: p. 12-18.
Alruhaili, A., et al., Development of a CZT drift ring detector for X and gamma ray spectroscopy. Journal of Instrumentation, 2015. 10.
Lohstroh, A., et al., Cadmium zinc telluride based infrared interferometry for X-ray detection. Applied Physics Letters, 2015. 106(6).
Leming, E., et al., A GEANT4 Monte Carlo simulation to describe the time response of a coupled SiPM and LYSO detection system. Journal of Instrumentation, 2014. 9.
Alruhaili, A., et al., Performance characteristics of CdTe drift ring detector. Journal of Instrumentation, 2014. 9.
Buis, C., et al., Effects of dislocation walls on charge carrier transport properties in CdTe single crystal. Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2014. 735: p. 188-192.
Abubakar, Y.M., A. Lohstroh, and P. Sellin, Semiconductor Neutron Detector for Harsh Radiation Applications. 2014 Ieee Nuclear Science Symposium and Medical Imaging Conference (Nss/Mic), 2014.
Schirru, F., et al., X-ray induced photocurrent characteristics of CVD diamond detectors with different carbon electrodes. Journal of Instrumentation, 2013. 8.
Bryant, P.A., A. Lohstroh, and P.J. Sellin, Electrical Characteristics and Fast Neutron Response of Semi-Insulating Bulk Silicon Carbide. Ieee Transactions on Nuclear Science, 2013. 60(2): p. 1432-1435.
Avella, P., et al., A study of timing properties of Silicon Photomultipliers. Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2012. 695: p. 257-260.
Schirru, F., et al., Development of large area polycrystalline diamond detectors for fast timing application of high-energy heavy-ion beams. Journal of Instrumentation, 2012. 7.
Chaudhuri, S.K., et al., Digital pulse height correction in HgI2 gamma-ray detectors. Journal of Instrumentation, 2012. 7.
Abdel-Rahman, M.A.E., et al., The X-ray detection performance of polycrystalline CVD diamond with pulsed laser deposited carbon electrodes. Diamond and Related Materials, 2012. 22: p. 70-76.
Blackie, D., et al., Exploration of the Pockels Effect for Radiation Detection Applications. 2012 Ieee Nuclear Science Symposium and Medical Imaging Conference Record (Nss/Mic), 2012: p. 402-404.
Abdel-Rahman, M.A.E., A. Lohstroh, and P.J. Sellin, The effect of annealing on the X-ray induced photocurrent characteristics of CVD diamond radiation detectors with different electrical contacts. Physica Status Solidi a-Applications and Materials Science, 2011. 208(9): p. 2079-2086.
Jeynes, C., R.P. Webb, and A. Lohstroh, Ion Beam Analysis: A Century of Exploiting the Electronic and Nuclear Structure of the Atom for Materials Characterisation. Reviews of Accelerator Science and Technology, Vol 4: Accelerator Applications in Industry and the Environment, 2011. 4: p. 41-82.
Lohstroh, A., et al., The effect of fast neutron irradiation on the performance of synthetic single crystal diamond particle detectors. Diamond and Related Materials, 2010. 19(7-9): p. 841-845.
Ozsan, M.E., et al., Chemical etching and surface oxidation studies of cadmium zinc telluride radiation detectors. Surface and Interface Analysis, 2010. 42(6-7): p. 795-798.
Prekas, G., et al., Investigation of the internal electric field distribution under in situ x-ray irradiation and under low temperature conditions by the means of the Pockels effect. Journal of Physics D-Applied Physics, 2010. 43(8).
Sellin, P.J., et al., Real time Imaging of the Electric field Distribution in CdZnTe at low temperature. Nuclear Radiation Detection Materials-2009, 2010. 1164: p. 15-+.
Gkoumas, S., A. Lohstroh, and P.J. Sellin, Low temperature time of flight mobility measurements on synthetic single crystal diamond. Diamond and Related Materials, 2009. 18(11): p. 1338-1342.
Xu, Y., et al., Comparison of the x-ray spectroscopy response and charge transport properties of semi-insulating In/Al doped CdZnTe crystals. Journal of Applied Physics, 2009. 105(8).
Veale, M.C., et al., Ion Beam Induced Charge Studies of CdZnTe Grown by Modified Vertical Bridgman Method. Ieee Transactions on Nuclear Science, 2008. 55(6): p. 3741-3745.
Lohstroh, A., et al., Ion beam induced charge (IBIC) irradiation damage study in synthetic single crystal diamond using 2.6 MeV protons. Physica Status Solidi a-Applications and Materials Science, 2008. 205(9): p. 2211-2215.
Sellin, P.J., et al., Ion beam induced charge imaging of charge transport in CdTe and CdZnTe. Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, 2008. 266(8): p. 1300-1306.
Lohstroh, A., et al., High gain observed in X-ray induced currents in synthetic single crystal diamonds. Physica Status Solidi a-Applications and Materials Science, 2007. 204(9): p. 3011-3016.
Sellin, P.J., et al., Charge transport in polycrystalline and single crystal synthetic diamond using ion beam induced charge imaging. Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, 2007. 260(1): p. 293-298.
Veale, M.C., et al., X-ray spectroscopy and charge transport properties of CdZnTe grown by the vertical Bridgman method. Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2007. 576(1): p. 90-94.
Baier, N., et al., EBIC and IBIC imaging on polyerystalline CdTe. Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2007. 576(1): p. 5-9.
Sellin, P.J., et al., IBIC characterization of charge transport in CdTe : Cl. Semiconductors, 2007. 41(4): p. 395-401.
Parkin, J., et al., alpha Particle response of undoped CdMnTe. Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2007. 573(1-2): p. 220-223.
Lohstroh, A., et al., Mapping of polarization and detrapping effects in synthetic single crystal chemical vapor deposited diamond by ion beam induced charge imaging. Journal of Applied Physics, 2007. 101(6).
Lohstroh, A., et al., Effect of dislocations on charge carrier mobility-lifetime product in synthetic single crystal diamond. Applied Physics Letters, 2007. 90(10).
Wang, S.G., P. Sellin, and A. Lohstroh, Temperature-dependent hole detrapping for unprimed polycrystalline chemical vapor deposited diamond. Applied Physics Letters, 2006. 88(2).
Sellin, P.J., et al., Drift mobility and mobility-lifetime products in CdTe : Cl grown by the travelling heater method. Ieee Transactions on Nuclear Science, 2005. 52(6): p. 3074-3078.
Wang, S., P. Sellin, and A. Lohstroh, Alpha particle transient response of a polycrystalline diamond detector. Carbon, 2005. 43(15): p. 3167-3171.
Davies, A.W., et al., Spatial uniformity of electron charge transport in high resistivity CdTe. Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2005. 546(1-2): p. 192-199.
Wang, S.G., et al., The effects of plasma post-treatment on the photoresponsivity of CVD diamond UV photodetectors. Diamond and Related Materials, 2005. 14(3-7): p. 541-545.
Wang, S.G., et al., Performance improvement of polycrystalline diamond ultraviolet photodetectors by room-temperature plasma treatment. Applied Physics Letters, 2005. 86(9).
Wang, S.G., et al., The fabrication and performance of CVD diamond-based X-ray detectors. Pricm 5: The Fifth Pacific Rim International Conference on Advanced Materials and Processing, Pts 1-5, 2005. 475-479: p. 3605-3609.
Sellin, P.J., et al., Ion beam induced charge imaging of epitaxial GaN detectors. Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2004. 531(1-2): p. 82-86.
Simon, A., P.J. Sellin, and A. Lohstroh, IBIC imaging of intra-crystallite charge transport in CVD diamond at reduced temperature. Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, 2004. 219: p. 1022-1026.
Sellin, P.J., et al., Digital IBIC-new spectroscopic modalities for ion-beam-induced charge imaging. Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2004. 521(2-3): p. 600-607.
Lohstroh, A., P.J. Sellin, and A. Simon, High-resolution mapping of the mobility-lifetime product in CdZnTe using a nuclear microprobe.
Journal of Physics-Condensed Matter, 2004. 16(2): p. S67-S73.
Lohstroh, A., et al., Electronic relaxation in indium oxide films studied with perturbed angular correlations. Hyperfine Interactions, 2004. 159(1-4): p. 35-42.
Sellin, P., et al., The role of defects on CdTe detector performance. 2003 Ieee Nuclear Science Symposium, Conference Record, Vols 1-5, 2004: p. 3306-3310.
Kulinska, A., et al., Lithium insertion into In2S3 studied by perturbed gamma-gamma angular correlation. Journal of Solid State Chemistry, 2004. 177(1): p. 109-118.
Simon, A., et al., Ion beam indneed charge microscopy imaging of CVD diamond. Microscopy of Semiconducting Materials 2003, 2003(180): p. 449-452.
Vetter, U., et al., Lattice location studies of indium in Cr2O3. Hyperfine Interactions, 2001. 136: p. 607-612.
Dedryvere, R., et al., Lithium in In2S3. Hyperfine Interactions, 2001. 136: p. 479-484.