Research Interests

My research is focused on the crystal growth and synthesis of functional and quantum materials. In particular, my recent focus has been on the synthesis and characterisation of single-crystal compounds that host skyrmions or exotic magnetic spin textures. I utilise a large range of crystal growth techniques including chemical vapour transport, Bridgman technique, self-flux method, optical floating zone and the Czochralski technique. The physical properties of all the materials that I synthesise at Warwick are measured using a variety of techniques, including in-house magnetic, thermodynamic and transport measurements, as well as the use of international central facilities using x-ray diffraction, neutron scattering and muon spectroscopy techniques.

During my PhD, my research was focused on noncentrosymmetric superconducting systems. In particular, I am interested in superconductors where time-reversal symmetry breaking is also observed. My work involved the synthesis of high-quality polycrystalline and single-crystal samples that can then be characterised using a variety of low-temperature thermodynamic, transport and magnetisation measurements. I also used international central facilities to carry out neutron scattering, muon spectroscopy, and high magnetic field experiments. We primarily used muon spin rotation and relaxation techniques to look for unconventional superconducting states in our compounds.

A copy of my PhD thesis can be found through the following link: Experimental studies of noncentrosymmetric superconductorsLink opens in a new window

My Research Profile

I joined the Superconductivity and Magnetism group at the University of Warwick in 2015 as a postgraduate research student, where I undertook my PhD under the supervision of Prof. Martin Lees. I had previously completed my MPhys Physics degree at the University of St Andrews in 2015. I re-joined the Superconductivity and Magnetism group at the University of Warwick in the summer of 2019 as a Research Fellow, where I worked with Prof. Geetha Balakrishnan, as a part of The Skyrmion Project until winter 2021. After the Skyrmion Project continued to work as a Research Fellow working jointly with Prof. Geetha Balakrishnan, Prof. Martin Lees, Dr Oleg Petrenko and Prof. Paul Goddard on a broad range various research projects until 2024. I am currently an Assistant Professor in the Superconductivity and Magnetism group.

Research Projects

Recently Funded

• “Developing UK capabilities to synthesise low-cost laser materials for commercial applications" - EPSRC Impact Acceleration Account (2023).

Publication Highlights:

A full and up-to-date list of all my publications (including number of citations) can be found by visiting the databases linked to in the panel on the right.

J. Neethirajan, B. J. Daurer, M. Di Pietro Martínez, A.; Hrabec, L. Turnbull, R. Yamamoto, M. R. Ferreira, A. Štefančič, D. A. Mayoh, G. Balakrishnan, Z. Pei, P. Xue, L. Chang, E. Ringe, R. Harrison, S. Valencia, M. Kazemian, B. Kaulich, and C. Donnelly, Soft X-Ray Phase Nanomicroscopy of Micrometer-Thick Magnets Physical Review X 14, 031028 (2024).

D. A. Mayoh, A. Štefančič, M.R. Lees, G. Balakrishnan, Crystal growth of the R₂PdSi₃ (R= rare earth) materials using the optical floating zone technique, Journal of Crystal Growth, 2024, 127774 (2024).Link opens in a new window

C. Bigi, L. Qiao, C. Liu, P. Barone, M. C. Hatnean, G.-R. Siemann, B. Achinuq, D. A. Mayoh, G. Vinai, V. Polewczyk, D. Dagur, F. Mazzola, P. Bencok, T. Hesjedal, G. van der Laan, W. Ren, G. Balakrishnan, S. Picozzi, and P. D. C. King, Covalency, correlations, and interlayer interactions governing the magnetic and electronic structure of Mn₃Si₂Te₆, Physical Review B 108, 054419 (2023).Link opens in a new window

B. Edwards, O. Dowinton, A. E. Hall, P. A. E. Murgatroyd, S. Buchberger, T. Antonelli, G.-R. Siemann, A. Rajan, E. Abarca Morales, A. Zivanovic, C. Bigi, R. V. Belosludov, C. M. Polley, D. Carbone, D. A. Mayoh, G. Balakrishnan, M. S. Bahramy, and P. D. C. King, Giant valley-Zeeman coupling in the surface layer of an intercalated transition metal dichalcogenide, Nature Materials 22, 459 (2023).Link opens in a new window

L. Powalla, M. T. Birch, K. Litzius, S. Wintz, F. S. Yasin, L. A. Turnbull, F. Schulz, D. A. Mayoh, G. Balakrishnan, M. Weigand, X. Yu, K. Kern, G. Schütz, and M. Burghard, Seeding and Emergence of Composite Skyrmions in a van der Waals Magnet, Advanced Materials 2023, 35, 2208930 (2023).Link opens in a new window

D. A. Mayoh, J. Bouaziz, A. E. Hall, J. B. Staunton, M. R. Lees, and G. Balakrishnan, Giant topological and planar Hall effect in Cr_1/3NbS₂, Physical Review Research 4, 013134 (2022).Link opens in a new window

D. A. Mayoh, S. J. R. Holt, T. Takabatake, G. Balakrishnan, and M. R. Lees, Anisotropic superconductivity and unusually robust electronic critical field in single crystal La₇Ir₃, Physical Review Materials 5, 114803 (2021).Link opens in a new window

D. A. Mayoh, G. D. A wood, S. J. R. Holt, G. Beckett, E. J. L. Dekker, M. R. Lees, and G. Balakrishnan, Effects of Fe Deficiency and Co Substitution in Polycrystalline and Single Crystal of Fe₃GeTe₂, Crystal Growth & Design 21, 6786 (2021).Link opens in a new window

P. K. Biswas, S.K. Ghosh, J. Z. Zhao, D. A. Mayoh, N. D. Zhigadlo, X. Xu, C. Baines, A. D. Hillier, G. Balakrishnan, and M. R. Lees, Chiral Singlet Superconductivity in the weakly correlated metal LaPt₃P, Nature Communications 12, 2504 (2021).

Recent Conference Highlights:

Invited Talks

• "Exploring Superconductivity in Time-Reversal Symmetry Breaking Hexagonal Noncentrosymmetric Superconductors" M²S Conference, Vancouver, Canada (2022).
• "Exploring Unconventional superconductivity in noncentrosymmetric compounds", Physics Colloquium Series, Technische Universität Braunschweig (2021).
• "Chiral Magnetism and the nature of magnetic ordering in the intercalated transition metal dichalcogenides", Theoretical and Experimental Magnetism Meeting, Online Conference (2021).

Oral Presentations:

• "Crystal growth and magnetic properties of rare-earth (RE) palladium silicides, RE₂PdSi₃" International Conference on crystal growth and epitaxy, Naples, Italy (2023).
• "Effects of Fe Deficiency and Co Substitution in Single Crystals of Fe₃GeTe₂" International Conference on crystal growth and epitaxy, Naples, Italy (2023).
• "Magnetic properties of the intercalated transition metal dichalcogenide Fe_1/3TaS₂" Condensed Matter and Quantum Matter, Birmingham, UK (2023).
• "Anisotropic Superconductivity and unusually robust electronic critical field in single crystal La₇Ir₃" American Physical Society March Meeting, Chicago, USA (2022).
• "Chiral magnetism and the Hall effect in Cr_1/3NbS₂" CRIM 2021: Magnetic Skyrmions workshop (2021).
• "Exploring superconductivity using μSR in hexagonal noncentrosymmetric superconductors", Condensed Matter and Quantum Materials, Online Conference (2021).

Poster Presentations:

• APS March meeting, Chicago, USA (2022).
• UK Neutron and Muon Science and User Meeting, Warwick, UK (2018 & 2019).
• Superconductivity Day, Liverpool, UK (2017).

Teaching Duties

I am actively involved in the undergraduate teaching through tutoring and final year research projects.

During my PhD I was a demonstrator and marker for the 1^st Year Physics Teaching Laboratory and 1^st Year Electronics Laboratory between 2015 and 2019. I was honoured to be selected as a commendee for the Warwick Awards for Teaching Excellence for Postgraduates who Teach 2018.

Public Engagement, Outreach and Widening Participation

I help run a series of workshops on superconducting 'levitation'. As part of this program, I deliver the workshops at the University of Warwick, local schools and at science events. The levitation workshop aims to explain the importance of superconductivity and magnetism in every day life. We demonstrate the stark changes that occur to the physical properties of materials when we cool them down using cryogenic liquids.

Events and activities

Here's a list with some of the recent public engagement, widening participation and outreach events and activities in which I have been involved.

XMaSLink opens in a new window:

• XMaS Science Gala (2020)Link opens in a new window

• XMaS Science Gala (2019).

• XMaS Science Gala (2018).

Science Festivals & Family Days:

• Girl Guiding (Brownies) Science Day (2018)Link opens in a new window
• Warwick Family Days (2018)Link opens in a new window.
• The Big Bang UK Young Scientists & Engineers Fair (2017 to Present)Link opens in a new window.
• Festival of the Imagination (2015)Link opens in a new window.
• Physics in the Field Demonstrator, Institute of Physics (2012)

University Open Days:

• University of Warwick, Physics Department (2015- Present)
• University of St Andrews, School of Physics and Astronomy (2010- 2015)

Other Professional Activities:

• Reviewer for Scientific Journals including Physical Review Letters, Physical Review B, Physical Review Materials, Physica Status Solidi and Journal of Crystal Growth.
• Health and Safety Committee - Representative of Chemical Handling and Chemical Storage (since 2021)
• Member of the Institute of Physics (IOP) (Since 2010)
• Co-organiser of the IOP Conference for Astronomy and Physics Students (CAPS) in St Andrews in 2014.

Below are a list of courses/training schools that I took during my postgraduate studies:

• ISIS Neutron Training School 2016
• ISIS Muon Training School 2016
• Diamond DTC Module: Properties & Characterisation Materials