Tutorial Fellow and Praelector in Physics; Professor of Physics; Financial Adviser
I teach a number of different courses in college including 2nd year thermal physics, 2nd year statistical mechanics, 3rd year condensed matter physics, usually in tutorial groups of between 2 and 4 students. I am particularly keen to relate the material to real world situations and applications.
In the department I teach the 4th year condensed matter physics option including running classes for Univ undergraduates studying this course. I supervise the thermal physics and condensed matter physics sections of the practical course where we have developed a number of more sophisticated experiments which are also used for project research.
I also teach part of the first year in the Oxford Sustainable Photovoltaics CDT.
My research covers both fundamental and applied aspects of semiconductor physics. I have a longstanding interest in the properties of semiconductors in very high magnetic fields and phenomena such as the quantum Hall effect and the magneto-optical properties of semiconductors. The most recent examples of this are a number of studies of the family of novel perovskite semiconductors which have been developed in Oxford as low-cost high-efficiency solar cells. This work is often done in collaboration with the European High Magnetic Field laboratories in Toulouse, and Grenoble.
I have also been exploring the properties of the carbon based nanomaterials, graphene and carbon nanotubes. In addition to measuring their basic properties I have been developing their use as electrodes in perovskite based solar cells and making transparent conducting films. Our cells have currently achieved efficiencies of over 18% and can be deposited cheaply onto glass. In collaboration with the National Physical Laboratory we have shown that graphene is an excellent material to use for the development of the quantum Hall effect as the national resistance standard.
A selection of my publications is listed below. For a complete list, and links to the papers, see physics.ox.ac.uk
Dopant-Free Planar n–i–p Perovskite Solar Cells with Steady-State Efficiencies Exceeding 18%
SN Habisreutinger , B Wenger, HJ Snaith and RJ Nicholas, ACS Energy Lett., (2017), 2 622–628
Determination of the exciton binding energy and effective masses for methylammonium and formamidinium lead tri-halide perovskite semiconductors
K Galkowski, A Mitioglu, A Miyata, P Plochocka, O Portugall, GE Eperon, JTW Wang, T Stergiopoulos, SD Stranks, HJ Snaith and RJ Nicholas, Energy and Environ. Sci. 9 (2016) 962, DOI: 10.1039/C5EE03435C
Efficient perovskite solar cells by metalion doping
JT-W Wang, ZP Wang, ZP S Pathak, W Zhang, DW deQuilettes, F Wisnivesky-Rocca-Rivarola, J Huang, PK Nayak, JB Patel, Hanis A Mohd Yusof, Yana Vaynzof, R Zhu, I Ramirez, J Zhang, C Ducati, C Grovenor, MB Johnston, DS Ginger, RJ Nicholas, HJ Snaith, Energy and Environ. Sci. 9 (2016) 2892, DOI: 10.1039/c6ee01969b
Physics of a disordered Dirac point in epitaxial graphene from temperature-dependent magnetotransport measurements
J Huang, JA Alexander-Webber, AMR Baker, TJBM Janssen, A Tzalenchuk, V Antonov, T Yager, S Lara-Avila, S Kubatkin, Rositsa Yakimova, RJ Nicholas, Physical Review B 92, 075407 (2015), doi:10.1103/PhysRevB.92.075407
Direct measurement of the exciton binding energy and effective masses for charge carriers in organic-inorganic tri-halide perovskites,
A. Miyata, A Mitioglu, P. Plochocka, O. Portugal, JTW Wang, SD Stranks, HJ Snaith and RJ Nicholas, Nature Physics 11 582-7, (2015) DOI: 10.1038/NPHYS3357
Carbon Nanotube/Polymer Composites as a Highly Stable Hole Collection Layer in Perovskite Solar Cells, SN Habisreutinger, T Leijtens, GE Eperon, SD Stranks, RJ Nicholas and HJ Snaith, Nano Letters, 14 5561-5568 (2014), DOI: 10.1021/nl501982b
Low-Temperature Processed Electron Collection Layers of Graphene/TiO2 Nanocomposites in Thin Film Perovskite Solar Cells,
JTW Wang, JM Ball, EM Barea, A Abate, JA Alexander-Webber, J Huang, M Saliba, I Mora-Sero, J Bisquert, HJ Snaith and RJ Nicholas, Nano Letters 14 724-730, (2014), DOI: 10.1021/nl403997a
Phase Space for the Breakdown of the Quantum Hall Effect in Epitaxial Graphene
JA Alexander-Webber, AMR Baker, TJBM Janssen, A Tzalenchuk, S Lara-Avila, S Kubatkin, R Yakimova, BA Piot, DK Maude and RJ Nicholas, Phys. Rev. Lett. 111 (2013) 096601
Highly selective dispersion of single-walled carbon nanotubes using aromatic polymers
A. Nish, J-Y. Hwang, J. Doig and RJ Nicholas, Nature Nanotechnology, 2 640 (2007) DOI: 10.1038/nnano.2007.290