Personal Biography

I am Professor of Physics at Oxford's Department of Physics and have been a Fellow of Corpus since 2002. I obtained my PhD in Physics from the University of New South Wales (Sydney, Australia) working on how electrons behave in quantum-confined systems. In 1999 I joined the Cavendish Laboratory at the University of Cambridge, where I was instrumental in setting up a new programme of research on the spectroscopy of semiconductors in the far-infrared ("terahertz") region of the electromagnetic spectrum. On arriving at Oxford in 2002 I established and currently lead a research group specialising in high-frequency semiconductor devices, as well as semiconductor charge dynamics and spectroscopy. I have made an important contribution towards understanding the emission of terahertz radiation from semiconductors, developed new photonic materials and devices and am an expert on electron dynamics in semiconductor nanostructures. My work has been recognised by a series of prizes including the Harrie Massey Medal, Friedrich Wilhelm Bessel Research Award, and IUMRS Somiya Award. I am also a Clarivate Highly Cited Researcher.

Research and Teaching

I am interested in the physics of charge dynamics in semiconductors and light matter interactions. My research stretches from fundamental physics to real-world applications and encompass the fields of terahertz (THz) science and technology, semiconductor nanostructures and metal halide perovskite optoelectronics. For example I have studied charge-carrier dynamics in nanoscale semiconductors by single-cycle terahertz probes, developing both instrumentation and new theories to uncover the underlying physics. Knowledge gained from my spectroscopic studies of fundamental charge dynamics in nano-semiconductors has led to the invention of novel ultra-high-speed photonic devices. Such devices include the first photoconductive THz detectors based on a single nanowire and an ultrafast terahertz modulator with picosecond switching times. My research group has also created a novel process for vapour deposition of metal halide perovskite semiconductors. This work was key to the creation of the first perovskite solar cell based on an efficient planar heterojunction architecture, now the gold standard in this area. The vapour deposition method he created has outstanding promise for the large-scale industrial production of cheap and high efficiency solar cells for clean energy conversion.

An introduction to my research may be found at

www-thz.physics.ox.ac.uk.

Google Scholar Profile: EM-j_L4AAAAJ

ORCID 0000-0002-0301-8033

I tutor physics at all levels of the undergraduate course. I currently tutor Corpus students in Electromagnetism, Quantum Mechanics, Atomic Physics, Condensed Matter Physics, Laser Physics and Optics. For Oxford Physics my teaching responsibilities include lecturing on band theory and the electronic properties of solids.

Selected Publications

Three-dimensional cross-nanowire networks recover full terahertz state

K Peng, D Jevtics, F Zhang, S Sterzl, DA Damry, MU Rothmann, B Guilhabert, MJ Strain, HH Tan, LM Herz, L Fu, MD Dawson, A Hurtado, C Jagadish, MB Johnston

Science, 368:510--513 (2020) [ doi:10.1126/science.abb0924 ]

Efficient planar heterojunction perovskite solar cells by vapour deposition

M Liu, MB Johnston, HJ Snaith

Nature, 501:395 (2013) [ doi:10.1038/nature12509 ]

Single nanowire photoconductive terahertz detectors

K Peng, P Parkinson, L Fu, Q Gao, N Jiang, YN Guo, F Wang, HJ Joyce, JL Boland, HH Tan, C Jagadish, MB Johnston

Nano letters 15: 206-210 (2014) [ doi:10.1021/nl5033843 ]

An ultrafast switchable terahertz polarization modulator based on III–V semiconductor nanowires

SA Baig, JL Boland, DA Damry, HH Tan, C Jagadish, HJ Joyce, MB Johnston

Nano letters 17: 2603-2610 (2017) [ doi:10.1021/acs.nanolett.7b00401 ]

Influence of interface morphology on hysteresis in vapor‐deposited perovskite JB Patel, J Wong‐Leung, S van Reenen, N Sakai, JTW Wang, ES Parrott, M Liu, HJ Snaith, LM Herz, MB Johnston

Advanced Electronic Materials 3 (2), 1600470 (2017) [ doi:10.1002/aelm.201600470 ]

Modulation doping of GaAs/AlGaAs core–shell nanowires with effective defect passivation and high electron mobility

JL Boland, S Conesa-Boj, P Parkinson, G Tütüncüoglu, F Matteini, D Rüffer, A Casadei, F Amaduzzi, F Jabeen, CL Davies, HJ Joyce, LM Herz, A Fontcuberta i Morral, MB Johnston

ecte Nano letters 15:1336-1342 (2015) [ doi:10.1021/nl504566t ]

A mixed-cation lead mixed-halide perovskite absorber for tandem solar cells

DP McMeekin, G Sadoughi, W Rehman, GE Eperon, M Saliba, Maximilian T Hörantner, A Haghighirad, N Sakai, L Korte, B Rech, MB Johnston, LM Herz, HJ Snaith

Science 351:151-155 (2016) [ doi:10.1126/science.aad5845 ]

Ultralow surface recombination velocity in InP nanowires probed by terahertz spectroscopy

HJ Joyce, J Wong-Leung, CK Yong, CJ Docherty, S Paiman, Q Gao, HH Tan, C Jagadish, J Lloyd-Hughes, LM Herz, MB Johnston

Nano Lett., 12:5325-5330 (2012) [ doi:10.1021/nl3026828 ]

Carrier Lifetime and Mobility Enhancement in Nearly Defect-Free Core--Shell Nanowires Measured Using Time-Resolved Terahertz Spectroscopy,

P Parkinson, HJ Joyce, Q Gao, HH Tan, X Zhang, J Zou, C Jagadish, LM Herz, MB Johnston

Nano Lett., 9:3349-3353 (2009) [ doi:10.1021/nl9016336 ]

Extreme sensitivity of graphene photoconductivity to environmental gases

CJ Docherty, CT Lin, HJ Joyce, RJ Nicholas, LM Herz, LJ Li, MB Johnston

Nature Communications 3:1228 (2012) [ doi:10.1038/ncomms2235 ]

Simulation of terahertz generation at semiconductor surfaces,

MB Johnston, DM Whittaker, A Corchia, AG Davies, EH Linfield

Phys. Rev. B, 65:165301 (2002) [ doi:10.1103/PhysRevB.65.165301 ]

Full Publication List: https://scholar.google.co.uk/citations?user=EM-j_L4AAAAJ&hl=end Publications