Multi-component altermagnet: A general approach to generating multi-component structures with two-dimensional altermagnetism

TL;DR

This paper introduces a symmetry-based method to generate and identify stable two-dimensional altermagnetic materials with multi-component structures, expanding the pool of potential candidates for experimental realization.

Contribution

The authors develop a systematic approach combining symmetry analysis and first-principles calculations to generate and evaluate multi-component 2D altermagnetic structures, including previously unreported materials.

Findings

Identified new 2D altermagnetic candidates such as Cr2Si2S3Se3, Fe2P2S3Se3, and V2O2BrI3.

Demonstrated the stability of these candidates via phonon spectrum calculations.

Provided a general framework for designing stable multi-component altermagnetic materials.

Abstract

Altermagnetism, as an unconventional antiferromagnetism, exhibits collinear-compensated magnetic order in real space and spin-splitting band structure in reciprocal space. In this work, we propose a general approach to generating multi-component structures with two-dimensional altermagnetism, based on symmetry analysis. Specifically, by analyzing the space group of the crystal structures and their subgroups, we systematically categorize equivalent atomic positions and arrange them into orbits based on symmetry operations. Chemical elements are then allowed to occupy all atomic positions on these orbits, generating candidate structures with specific symmetries. We present a general technique for generating collinear-compensated magnetic order, characterized by the symmetrical interconnection between opposite-spin sublattices, and employ first-principles calculations to determine magnetic ground states of multi-component materials. This approach integrates symmetry analysis with the screening of altermagnetic configurations to evaluate the likelihood of candidates possessing altermagnetism. To verify the methodology, we provide examples of previously unreported 2D altermagnets, such as Cr2Si2S3Se3, Fe2P2S3Se3, and V2O2BrI3, and evaluate their dynamical stability by calculating the phonon spectrum. The results demonstrate the feasibility of our approach in generating stable multi-component structures with two-dimensional altermagnetism. Our research has significantly enriched the candidate materials for 2D altermagnet and provided a reference for experimental synthesis.