Dr Matthew Coak

School of Physics and Astronomy
Assistant Professor

Contact details

Email: m.j.coak@bham.ac.uk

Address: School of Physics and Astronomy
Physics East 207
University of Birmingham
Edgbaston
Birmingham
B15 2TT
UK

I am an experimental condensed-matter physicist specialising in high pressure techniques. My research programme focuses on 2D magnetic materials, and the effects of pressure in tuning them towards 3D systems by compressing their atomic planes together. I measure the accompanying changes in structural, magnetic and transport properties to search for new exotic phases and behaviour. As well as bulk materials my work also explores few-layer flakes of 2D materials and multi-material nanoscale heterostructures.

Qualifications

PhD in Experimental Condensed Matter Physics, University of Cambridge, 2017
MPhys combined 4 year Masters programme in Physics, University of Oxford, 2011

Biography

I completed my undergraduate degree in physics at the University of Oxford, with my masters thesis on the development of proximity-detector-oscillators for use in pulsed magnetic fields. Following this I moved on to a PhD at the University of Cambridge under Dr Siddharth Saxena, graduating in 2017. My specialisation was in the use of high pressure to tune quantum criticality in ferroelectric systems and Mott transitions in 2D insulating antiferromagnets.

My first postdoctoral position was in the Emergent Phenomena Group of the IBS Centre for Correlated Electron Systems at Seoul National University, under Prof Je-Geun Park. Here I headed the van-der-Waals materials team and continued my investigation into Mott transitions and the tuning of low-dimensional magnetism with pressure, including synchrotron and neutron scattering studies. I then joined the Superconductivity and Magnetism group at Warwick in March 2019. I worked with Dr Paul Goddard from 2019 to 2021 using pressure, magnetic fields and low temperatures to tune and study low-dimensional magnetic materials and superconductors. In 2022 I left Warwick to take up a position as a Senior Research Fellow working with Dr Mark Buitelaar in the Quantum Devices Group at University College London. Here I worked on new underlying technologies for qubits in a distributed quantum computer based on measurement-based entanglement.

I started as a Lecturer here at Birmingham in 2023, where I am heading a group doing extreme conditions measurements of 2D magnetic materials.

I was very grateful to be named as one of the Institute of Physics' Emerging Leaders 2019 - "the most exciting researchers of their generation, with the potential to revolutionise their fields".

Teaching

1st year Physics practical course

Research

Research interests

My research centres around identifying and synthesising interesting new two-dimensional magnetic materials, then controlling their properties by applying hydrostatic pressure. The best way to achieve this is to compress the material between two opposing diamonds in a Diamond Anvil Cell – which is then cooled to temperatures of a few degrees Kelvin and measurements made of how physical properties like electrical conduction, crystal structure or magnetism evolve.

Tuning like this allows us to explore physics and identify new useful states of matter that have not been seen in the natural world – then create new materials that display that new behaviour based on what we have learned.

As well as ‘bulk-scale’ materials physics I also work on nanoscale fabrication and measurement of new kinds of electronic devices, again tuning and controlling them to discover new quantum functional behaviour.

Other activities

SquidLab - Magnetic Background Subtraction Software

I am the lead developer on the 'SquidLab' software suite,for subtracting magnetic backgrounds in magnetisation data. SquidLab is written in Matlab, designed to be flexible and customisable, and is free to download with full editable source code under Academic Licence.

SquidLab is described in our recent Review of Scientific Instruments paper, and in the accompanying SciLight article for a general audience.

SquidLab download link

Publications

Jarvis, D. M., Coak, M. J., Hamidov, H., Haines, C. R. S., Lampronti, G. I., Liu, C., Deng, S., Daisenberger, D., Allan, D. R., Warren, M. R., Wildes, A. R. & Saxena, S. S. (2023), Comparative structural evolution under pressure of powder and single crystals of the layered antiferromagnet FePS₃, Physical Review B 107:054106

Götze, K., Pearce, M., Coak, M. J., Goddard, P., Grockowiak, A., Coniglio, W., Tozer, S. W., Graf, D. E., Maple, M. B., Ho, P-C., Brown, M. & Singleton, J. (2022), Pressure-induced shift of effective Ce valence, Fermi energy and phase boundaries in CeOs₄Sb₁₂, New Journal of Physics 24:043044

Sim, S., Yang, H., Kim, H-L., Coak, M. J., Itoh, M., Noda, Y. & Park, J-G. (2021), Sizable Suppression of Thermal Hall Effect upon Isotopic Substitution in SrTiO₃, Physical Review Letters 126:015901

Coak, M. J., Jarvis, D. M., Hamidov, H., Wildes, A. R., Paddison, J. A. M., Liu, C., Haines, C. R. S., Dang, N. T., Kichanov, S. E., Savenko, B. N., Lee, S., Kratochvílová, M., Klotz, S., Hansen, T. C., Kozlenko, D. P., Park, J-G. & Saxena, S. S (2021), Emergent Magnetic Phases in Pressure-Tuned van der Waals Antiferromagnet FePS₃, Physical Review X 11:011024

Curley, S. P. M., Huddart, B. M., Kamenskyi, D., Coak, M. J., Williams, R. C., Ghannadzadeh, S., Schneider, A., Okubo, S., Sakurai, T., Ohta, H., Tidey, J. P., Graf, D., Clark, S. J., Blundell, S. J., Pratt, F. L., Telling, M. T. F., Lancaster, T., Manson, J. L. & Goddard, P. A. (2021), Anomalous magnetic exchange in a dimerized quantum magnet composed of unlike spin species, Physical Review B 104:214435

Valenta, J., Kratochvílová, M., Míšek, M., Carva, K., Kaštil, J., Doležal, P., Opletal, P., Čermák, P., Proschek, P., Uhlířová, K., Prchal, J., Coak, M. J., Son, S., Park, J-G. & Sechovský, V. (2021), Pressure-induced large increase of Curie temperature of the van der Waals ferromagnet VI₃, Physical Review B 103:054424

Coak, M. J., Haines, C. R. S., Liu, C., Rowley, S. E., Lonzarich, G. G. & Saxena, S. S. (2020), Quantum critical phenomena in a compressible displacive ferroelectric, Proceedings of the National Academy of Sciences 117:12707

Coak, M. J., Liu, C., Jarvis, D. M., Park, S., Cliffe, M. J. & Goddard, P. A (2020), Coak, M. J., Liu, C., Jarvis, D. M., Park, S., Cliffe, M. J. & Goddard, P. A, SquidLab - A user-friendly program for background subtraction and fitting of magnetization data, Review of Scientific Instruments 91:023901

Son, S., Shin, Y. J., Zhang, K., Shin, J., Lee, S., Idzichi, H., Coak, M. J., Kim, H., Kim, J., Kim, J. H., Kim, M., Kim, D., Kim, P. & Park, J-G. (2020), Strongly adhesive dry transfer technique for van der Waals heterostructure, 2D Materials 7:041005

Kim, J., Son, S., Coak, M. J., Hwang, I., Lee, Y., Zhang, K. & Park, J-G. (2020), Observation of plateau-like magnetoresistance in twisted Fe₃GeTe₂/Fe₃GeTe₂ junction, Journal of Applied Physics 128:093901

Graham, J. N., Coak, M. J., Son, S., Suard, E., Park, J-G., Clark, L. & Wildes, A. R. (2020), Local nuclear and magnetic order in the two-dimensional spin glass Mn_0.5Fe_0.5PS₃, Physical Review Materials 4:084401

Park, S., Kang, S., Kim, H., Lee, K. H., Kim, P., Sim, S., Lee, N., Karuppannan, B., Kim, J., Kim, J., Sim, K. I., Coak, M. J., Noda, Y., Park, C-H., Kim, J. H. & Park, J-G. (2020), Kagome van-der-Waals Pd₃P₂S₈ with flat band, Scientific Reports 10:1

Coak, M. J., Haines, C. R. S., Liu, C., Guzmán-Verri, G. G. & Saxena, S. S (2019), Pressure dependence of ferroelectric quantum critical fluctuations, Physical Review B 100:214111

Coak, M. J., Haines, C. R. S., Liu, C., Jarvis, D. M., Littlewood, P. B. & Saxena, S. S. (2019), Isostructural Mott transition in 2D honeycomb antiferromagnet V_0.9PS₃, npj Quantum Materials 4:38

Coak, M. J., Kim, Y-H., Yi, Y. S., Son, S., Lee, S. K. & Park, J-G. (2019), Electronic and vibrational properties of the two-dimensional Mott insulator V_0.9PS₃ under pressure, Physical Review B, 100:035120

Coak, M. J., Jarvis, D. M., Hamidov, H., Haines, C., Alireza, P. L., Liu, C., Son, S., Hwang, I., Lampronti, G. I., Daisenberger, D., Nahai-Williamson, P., Wildes, A., Saxena, S. S. & Park, J-G (2019), Tuning dimensionality in van-der-Waals antiferromagnetic Mott insulators TMPS₃, Journal of Physics: Condensed Matter 32:124003

Hwang, I., Coak, M. J., Lee, N., Ko, D-S., Oh, Y., Jeon, I., Son, S., Zhang, K., Kim, J. & Park, J-G. (2019), Hard ferromagnetic van-der-Waals metal (Fe,Co)₃GeTe₂: a new platform for the study of low-dimensional magnetic quantum criticality, Journal of Physics: Condensed Matter 31:50

Kim, H-L., Coak, M. J., Baglo, J. C., Murphy, K., Hill, R. W., Sutherland, M., Hatnean, M. C., Balakrishnan, G. & Park, J-G. (2019), Modular thermal Hall effect measurement setup for fast-turnaround screening of materials over wide temperature range using capacitive thermometry, Review of Scientific Instruments 90:103904

Son, S., Coak, M. J., Lee, N., Kim, J., Kim, T. Y., Hamidov, H., Cho, H., Liu, C., Jarvis, D. M., Brown, P. A. C., Kim, J. H., Park, C-H., Khomskii, D. I., Saxena, S. S. & Park, J-G. (2019), Bulk properties of the van der Waals hard ferromagnet VI₃, Physical Review B 99:041402(R)

Haines, C. R. S., Coak, M. J., Wildes, A. R., Lampronti, G. I., Liu, C., Nahai-Williamson, P., Hamidov, H., Daisenberger, D. & Saxena, S. S. (2018), Pressure-Induced Electronic and Structural Phase Evolution in the van der Waals Compound FePS₃, Physical Review Letters 121:266801

Yogi, A., Sathish, C. I., Sim, H., Coak, M. J., Noda, Y. & Park, J-G. (2018), Symmetry breaking and unconventional charge ordering in single crystal Na_2.7Ru₄O₉, Physical Review B 98:085113

Ghannadzadeh, S., Coak, M. J., Franke, I., Goddard, P. A., Singleton, J. & Manson, J. L. (2011), Measurement of magnetic susceptibility in pulsed magnetic fields using a proximity detector oscillator, Review of Scientific Instruments 82:113902