Emergence of Topological Bimerons in Monolayer CrSBr

TL;DR

This study uses atomistic simulations to reveal the formation of metastable topological bimerons in monolayer CrSBr, driven by Dzyaloshinskii-Moriya interactions and controlled by cooling rates, highlighting CrSBr as a promising platform for topological spin textures.

Contribution

It uncovers the emergence of topological bimerons in monolayer CrSBr and links their formation to Dzyaloshinskii-Moriya interactions and cooling dynamics, advancing understanding of topological spin textures in 2D magnets.

Findings

Topological bimerons emerge below a certain temperature T* in CrSBr.

Dzyaloshinskii-Moriya interaction causes bimeron formation.

Bimeron density follows Kibble-Zurek scaling with cooling rate.

Abstract

The rich and fascinating physics of topological spin textures in van der Waals two-dimensional magnets has motivated recent growing interests, though a comprehensive understanding remains elusive. Here, in atomistic simulations on monolayer CrSBr, we find two magnetic phases emerging under non-equilibrium conditions at distinct temperatures, a standard ferromagnetic transition Tc and a lower temperature T*. Moreover, the real-space analysis of the spin texture reveals the emergence of metastable topological bimeron defects below T*, showing an algebraic-like decaying spin-spin correlation function. The Dzyaloshinskii-Moriya interaction, induced by the local site asymmetry in the centrosymmetric CrSBr monolayer, is proved to be the origin of the bimerons formation. Furthermore, the increasing bimerons density upon increasing the cooling rate follows a Kibble-Zurek behavior, suggesting a handle to drive and control topological bimerons below T*. Our results put forward CrSBr as an important candidate for the investigation of the dynamical behavior of bimerons in vdW magnets.