Background

I completed a Master of Physics (MPhys) degree at the University of Warwick in 2024. In the summer of 2018 I completed an eight week research project through the Undergraduate Research Support Scheme (URSS) on Skyrmionic materials under the supervision of Prof. Geetha BalakrishnanLink opens in a new window. In 2023 I completed my PhD in Physics researching unconventional superconductivity under the supervision of Dr Martin LeesLink opens in a new window, co-supervised by Prof. Geetha BalakrishnanLink opens in a new window.

Research Interests

My PhD centred on exploring the unconventional behaviour of a range of superconducting materials. The unconventionality can arise from any of the following: the pairing mechanism of the electrons within the Cooper pairs, the symmetry of the Cooper pair wavefunction, and the group symmetries that are broken when transitioning from the normal to the superconducting state.

This project aimed to better understand the underlying mechanisms that drive unconventional superconductivity in new materials, which have the potential to be used in a range of applications. Previously studied materials were also explored to gain a new and better insight into their exotic properties.

The project involved preparing polycrystalline and single crystal samples using a range of crystal growth techniques, and studying their normal and superconducting state behaviour through structural, thermodynamic, magnetic and transport measurements, at high magnetic fields and at low temperatures. Materials of interest exhibit properties such as strong spin-orbit coupling or a noncentrosymmetric crystal structure. These materials were also investigated at national and international facilities using techniques such as muon spectroscopy, which investigates time reversal symmetry breaking.

Where am I now?

David is currently a research fellow in the quantum devices group in the London Centre for Nanotechnology, led by Dr Mark Buitelaar. My research focus is performing radio-frequency reflectometry measurements at low temperatures on solid-state devices that can be used as quantum computational hardware. In particular, measurement-based entanglement of spin qubits in spatially separated arsenic dopants in silicon will be explored. The As nuclear spin will also be utilised for quantum memory. This project is in collaboration with the groups of Professor Neil Curson, Dr Taylor Stock, and Professor Sougato Bose.

PhD Thesis

David G. C. Jonas - Preparation and experimental studies into unconventional superconductivity in metallic elements and binary intermetallic alloys. (click here for PDFLink opens in a new window)

Publications

D. G. C. Jonas, P. K. Biswas, A. D. Hillier, D. A. Mayoh, and M. R. Lees, Quantum muon diffusion and the preservation of time-reversal symmetry in the superconducting state of type-I rhenium, Physical Review B 105, L020503 (2022).Link opens in a new window

Conferences

Oral Presentations

"A muon‐spin relaxation study of type‐I rhenium investigating time‐reversal symmetry breaking in the superconducting state" UK Neutron and Muon Science and User Meeting (2022).

Poster Presentations

• ISIS Student Meeting, Virtual Meeting (2020)
• Condensed Matter and Quantum Materials IOP (2021)
• 15^th International Conference on Muon Spin Rotation, Relaxation and Resonance [MuSR2020] (2022)

Courses Taken

MPAGS

• Classical and Quantum Phase Transitions (2019/20)
• LabVIEW Core 1 (2019/20)
• LabVIEW Core 2 (2019/20)
• PX918 Electronic Structure Theory for Experiments and Models
• PX919 Quantum Chemistry

Teaching Experience

I supported second year undergraduate students as a demonstrator in the microprocessors laboratory from 2019 to 2022. I also demonstrated in the first year undergraduate electronics laboratory in 2022.

In November 2021 I was awarded the status of Associate Fellow of the Higher Education Academy (AFHEA)Link opens in a new window. The main aspect of this was a reflective narrative piece, in which I outlined my experience-based approaches to teaching and learning support in higher education, supported by literature. This was written within the UK Professional Standard Framework.

Current address

Physics Department
University College London
Gower Street
London
WC1E 6BT
United Kingdom

E-Mail:

d dot jonas at ucl dot ac dot uk

David's work at Warwick

If you have any questions about David's work at Warwick, please contact Martin LeesLink opens in a new window.