Dr. Sarah Jenkins

My research focuses on atomistic modelling of magnetic materials and spintronic devices. Specifically, the technologically relevant antiferromagnets IrMn3 and Mn2Au. These materials display ultra fast dynamics and due to their lack of stray fields can achieve extremely high areal densities giving them to potential to greatly outperform ferromagnets in spintronic devices. A large problem in the development of such devices is the detection and control of the magnetisation due to the lack of stray fields in the AFM. Electrical switching of AFM’s has recently been reported however the mechanisms behind these interactions are still to be uncovered. Using an atomistic spin model I have modelled the electrical switching and temperature dependance of the domain wall dynamics in Mn2Au to discover the switching times, domain wall widths and velocities.

My current research focuses on using machine learning to detect small defects in the magnetic properties of a material from videos even at temperatures above the curie temperature. The idea is to use an atomistic spin model to quantify changes in the anisotropy, exchange due to defects which can then be compared to experimental measurements.

I am a developer of the atomistic modelling software package VAMPIRE and have implemented hierarchical and atomistic dipole-dipole schemes as well as a micro magnetic code within the software package. I have also led three workshops on using VAMPIRE.

Publications:

Sarah Jenkins, Wei Jia Fan, Roxana Gaina, Roy W Chantrell, Timothy Klemmer, Richard FL Evans,Atomistic origin of exchange anisotropy in noncollinear –CoFe bilayers”, Physical Review B, 102, (2020) 

Sarah Jenkins, Roy W Chantrell, Richard FL Evans “The origin of exchange bias in multigranular non-collinear IrMn/CoFe thin films”, Physical Review B, 103, (2020)

Mathias Augustin, Sarah Jenkins, Richard F. L. Evans, Kostya S. Novoselov & Elton J. G. Santos, "Properties and dynamics of meron topological spin textures in the two-dimensional magnet CrCl3” Nature Communications, 12, (2020)

Dina Abdul Wahab, Mathias Augustin, Samuel Manas Valero, Wenjun Kuang, Sarah Jenkins, Eugenio Coronado, Irina V Grigorieva, Ivan J Vera‐Marun, Efrén Navarro‐Moratalla, Richard FL Evans, Kostya S Novoselov, Elton JG Santos, Quantum Rescaling, "Domain Metastability, and Hybrid Domain‐Walls in 2D CrI3 Magnets,” Advanced Materials, (2020)

Sarah Jenkins, R.F.L. Evans, Enhanced Finite size and interface mixing effects in IrMn ultrathin films, Journal of Applied Physics, 124, (2018)

Sarah Jenkins, Roy W Chantrell, Richard F.L. Evans, "Magnetic Anisotropy of the noncolinear AFM IrMn3", Physical Review B, 100, (2019)

Sarah Jenkins, Richard Evans, "Magnetic stray fields in nanoscale magnetic tunnel junctions”, Journal of Physics D , 53, (2019)

Sarah Jenkins, R.F.L. Evans, "Spin wave excitations in exchange biased IrMn/CoFe bilayers", Journal of Applied Physics, 128, (2020)

Richard Evans, L. Rozsa,  Sarah Jenkins,  Unai Atxitia,  "Temperature scaling of two-ion anisotropy in pure and mixed anisotropy systems", Physical Review B, (2020)

Roberto Moreno, Samuel Poyser, Daniel Meilak, Andrea Meo, Sarah Jenkins, Vlado K Lazarov, Gonzalo Vallejo-Fernandez, Sara Majetich, Richard FL Evans ,"The role of faceting and elongation on the magnetic anisotropy of magnetite Fe3O4 nanocrystals", Scientific Reports, 10, (2020)