Micromagnetic modeling and imaging of vortex|meron structures in an oxide|metal heterostructure

Using micromagnetic simulations, we have modeled the formation of imprinted merons and antimerons in cobalt overlayers of different thickness (1--8 nm), stabilized by interfacial exchange with antiferromagnetic vortices in $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{Fe}}₂{\mathrm{O}}₃$. Structures similar to those observed experimentally could be obtained with reasonable exchange parameters, also in the presence of surface roughness. We produce simulated meron and antimeron images by magnetic force microscopy and nitrogen-vacancy center microscopy, and established signatures of these topological structures in different experimental configurations.