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arXiv · 1912.07511

Micromagnetic modelling and imaging of vortex|merons structures in an oxide|metal heterostructure

P. G. Radaelli·J. Radaelli·N. Waterfield-Price·R. D. Johnson
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Abstract

Using micromagnetic simulations, we have modelled the formation of imprinted merons and anti-merons in cobalt overlayers of different thickness (1-8 nm), stabilised by interfacial exchange with antiferromagnetic vortices in $α$-Fe2O3. Structures similar to those observed experimentally could be obtained with reasonable exchange parameters, also in the presence of surface roughness. We produce simulated meron|antimeron images by magnetic force microscopy (MFM) and nitrogen-vacancy (N-V) centre microscopy, and established signatures of these topological structures in different experimental configurations.

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P. G. Radaelli, J. Radaelli, N. Waterfield-Price, R. D. Johnson. 2020-04-15. Micromagnetic modelling and imaging of vortex|merons structures in an oxide|metal heterostructure. https://doi.org/10.1103/physrevb.101.144420

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