Anisotropic Dzyaloshinskii-Moriya interaction protected by D2d crystal symmetry in two-dimensional ternary compounds

TL;DR

This paper reveals that anisotropic Dzyaloshinskii-Moriya interaction, protected by D2d crystal symmetry, can exist in 2D ternary compounds, enabling the realization of various magnetic quasiparticles like antiskyrmions and bimerons.

Contribution

It is the first report of anisotropic DMI in 2D magnets, demonstrated through first-principles calculations and micromagnetic simulations in MCuX2 compounds.

Findings

Anisotropic DMI exists in MCuX2 due to D2d symmetry.

Ferromagnetic and antiferromagnetic skyrmions and bimerons can be stabilized.

D2d symmetry protects anisotropic DMI in 2D ternary compounds.

Abstract

Magnetic skyrmions, topologically protected chiral spin swirling quasiparticles, have attracted great attention in fundamental physics and applications. Recently, the discovery of two-dimensional (2D) van der Waals (vdW) magnets has aroused great interest due to their appealing physical properties. Moreover, both experimental and theoretical works have revealed that isotropic Dzyaloshinskii Moriya interaction (DMI) can be achieved in 2D magnets or ferromagnet-based heterostructures. However, 2D magnets with anisotropic DMI haven't been reported yet. Here, via using first-principles calculations, we unveil that anisotropic DMI protected by D2d crystal symmetry can exist in 2D ternary compounds MCuX2. Interestingly, by using micromagnetic simulations, we demonstrate that ferromagnetic (FM) antiskyrmions, FM bimerons, antiferromagnetic (AFM) antiskyrmions and AFM bimerons can be realized in MCuX2 family. Our discovery opens up an avenue to creating antiskyrmions and bimerons with anisotropic DMI protected by D2d crystal symmetry in 2D magnets.