Strain-driven skyrmion-bimeron switching in topological magnetic monolayer CrSeBr.

Skyrmion-bimeron switching is one of the most important phenomena in topological magnetism. Currently, it is usually realized by the annoying spin orientation vertical-reversal through magnetic field. Based on first-principles calculations and atomic spin simulations, we alternatively unveil that the switching between magnetic skyrmions and bimerons can be achieved in topological magnetic monolayer CrSeBr by external strain. The core mechanism of this switching is traced to the controllable magnetic anisotropy of monolayer CrSeBr influenced by the strain-engineered low-energy states around the Fermi level. We also introduce a parameter || as a criterion for judging the stability of magnetic skyrmions and bimerons, which can be adopted as a useful descriptor linking the presence of skyrmion-bimeron switching driven by strain. The underlying physics is discussed in detail. The predicted strain controlled skyrmion-bimeron switching may be interesting for topological magnetic devices.