Dr Freya Clementine Cruickshank Johnson
Dr Johnson is an 1851 Research Fellow in the Cavendish Laboratory, Department of Physics.
Dr Johnson is an 1851 Research Fellow in the Cavendish Laboratory, Department of Physics. Her research involves atomic-precision growth of antiferromagnetic thin films, advanced electronic and magnetic characterisation, and ultrafast spectroscopy, to develop materials for high speed, energy-efficient computing. These materials naturally operate at terahertz frequencies, which is one thousand times faster than current technologies, and may be switched using energy-efficient spin current that doesn’t produce waste heat. In addition, these materials host an electron wavefunction phase effect, known as Berry curvature, that causes these materials to exhibit anomalous physical properties not normally expected in antiferromagnets. These properties provide new opportunities to read and write the underlying spin state quickly and easily using a large variety of stimuli such as electric current, heat, light and strain.
Dr Johnson received her PhD from Imperial College London, followed by postdoctoral research at Imperial and at University College London. She is a member of the Spin and Topology working group in the Materials for Quantum Network. She is also a member of the Magnetism Committee at the Institute of Physics.
- F. Johnson, J. Zázvorka, L. Beran, D. Boldrin, L. F. Cohen, J. Zemen & M. Veis. Room-temperature weak collinear ferrimagnet with symmetry-driven large intrinsic magneto-optic signatures. Physical Review B 107, 014404, doi:10.1103/PhysRevB.107.014404 (2023).
- F. Johnson, J. Kimák, J. Zemen, Z. Šobáň, E. Schmoranzerová, J. Godinho, P. Němec, S. Beckert, H. Reichlová, D. Boldrin, J. Wunderlich & L. F. Cohen. Identifying the octupole antiferromagnetic domain orientation in Mn3NiN by scanning anomalous Nernst effect microscopy. Applied Physics Letters 120, 232402, doi:10.1063/5.0091257 (2022).
- F. Johnson, D. Boldrin, J. Zemen, D. Pesquera, J. Kim, X. Moya, H. Zhang, H. K. Singh, I. Samathrakis & L. F. Cohen. Strain dependence of Berry-phase-induced anomalous Hall effect in the non-collinear antiferromagnet Mn3NiN. Applied Physics Letters 119, 222401, doi:10.1063/5.0072783 (2021).
- 2023, Royal Commission for the Exhibition of 1851 Research Fellowship
- 2022, Solid State Thesis Prize
ORCID profile: https://orcid.org/0000-0001-6922-3032