Anisotropic Dzyaloshinskii-Moriya interaction and topological magnetism in two-dimensional magnets protected by P4-m2 crystal symmetry

TL;DR

This paper reveals how P4-m2 symmetry in 2D magnets induces anisotropic Dzyaloshinskii-Moriya interactions, leading to diverse topological spin textures like skyrmions and vortices, advancing the design of 2D topological magnetic materials.

Contribution

It introduces a family of 2D magnets with symmetry-protected anisotropic DMI and demonstrates the emergence of various topological spin configurations, expanding understanding of 2D topological magnetism.

Findings

Identification of P4-m2 symmetry-protected anisotropic DMI in 2D magnets.

Prediction of stable FM/AFM topological spin textures such as antiskyrmions.

Establishment of a general method to design anisotropic DMI using crystal symmetry.

Abstract

As a fundamental magnetic parameter, Dzyaloshinskii-Moriya interaction (DMI), has gained a great deal of attention in the last two decades due to its critical role in formation of magnetic skyrmions. Recent discoveries of two-dimensional (2D) van der Waals (vdW) magnets has also gained a great deal of attention due to appealing physical properties, such as gate tunability, flexibility and miniaturization. Intensive studies have shown that isotropic DMI stabilizes ferromagnetic (FM) topological spin textures in 2D magnets or their corresponding heterostructures. However, the investigation of anisotropic DMI and antiferromagnetic (AFM) topological spin configurations remains elusive. Here, we propose and demonstrate that a family of 2D magnets with P4-m2 symmetry-protected anisotropic DMI. More interestingly, various topological spin configurations, including FM/AFM antiskyrmion and AFM vortex-antivortex pair, emerge in this family. These results give a general method to design anisotropic DMI and pave the way towards topological magnetism in 2D materials using crystal symmetry.