Antichiral ferromagnetism

Filipp N Rybakov,Egor Babaev,Olle Eriksson,Anastasiia Pervishko

doi:10.1103/physrevb.104.l020406

Abstract

Here by combining a symmetry-based analysis with numerical computations we predict a new kind of magnetic ordering - antichiral ferromagnetism. The relationship between chiral and antichiral magnetic order is conceptually similar to the relationship between ferromagnetic and antiferromagnetic order. Without loss of generality, we focus our investigation on crystals with full tetrahedral symmetry where chiral interaction terms - Lifshitz invariants - are forbidden by symmetry. However, we demonstrate that leading chirality-related term leads to nontrivial smooth magnetic textures in the form of helix-like segments of alternating opposite chiralities. The unconventional order manifests itself beyond the ground state by stabilizing excitations such as domains and skyrmions in an antichiral form.

Highlights

By combining a symmetry-based analysis with numerical computations, we predict a different kind of magnetic ordering—antichiral ferromagnetism
We focus our investigation on crystals with full tetrahedral symmetry where chiral interaction terms—Lifshitz invariants—are forbidden by symmetry
By virtue of symmetry of the above-mentioned and other symmetric interactions, the reflection of modulated magnetic texture is defined by degenerate energy states with opposite chirality, where a certain chirality is a consequence of spontaneous symmetry breaking

Summary

Introduction

By combining a symmetry-based analysis with numerical computations, we predict a different kind of magnetic ordering—antichiral ferromagnetism. This term aims to reflect that spontaneous modulation of the magnetization direction m(r) appears in a way that both types of chirality (handedness) exist simultaneously, and alternate in space. We demonstrate that the leading chirality-related term leads to nontrivial smooth magnetic textures exhibiting antichirality.

Results

Conclusion