Skyrmions in square-lattice antiferromagnets

TL;DR

This paper discovers a new skyrmion-like phase in square-lattice antiferromagnets through simulations and theory, showing stable skyrmions can exist at finite temperatures, offering potential for data storage applications.

Contribution

It identifies a novel skyrmion-like phase in antiferromagnets and demonstrates its stability, expanding understanding of topological magnetic structures in these systems.

Findings

A new phase similar to skyrmions was found between spin-flop and spiral phases.

Isolated skyrmions are stabilized in finite systems at higher temperatures.

Stable skyrmions in antiferromagnets could serve as data carriers.

Abstract

The ground states of square lattice two-dimensional antiferromagnets with anisotropy in an external magnetic field are determined using Monte Carlo simulations and compared to theoretical analysis. We find a new phase in between the spin-flop and spiral phase that shows strong similarity to skyrmions in ferromagnetic thin films. We show that this phase arises as a result of the competition between Zeeman and Dzyaloshinskii-Moriya interaction energies of the magnetic system. Moreover, we find that isolated (anti-)skyrmions are stabilized in finite-sized systems, even at higher temperatures. The existence of thermodynamically stable skyrmions in square-lattice antiferromagnets provides an appealing alternative over skyrmions in ferromagnets as data carriers.