Spin density wave as a superposition of two magnetic states of opposite chirality and its implications

TL;DR

This paper investigates the origin of spin density waves in weakly frustrated magnetic solids, revealing they result from superpositions of chiral magnetic states and are influenced by lattice relaxation and magnetic anisotropy.

Contribution

It demonstrates that SDWs arise from superpositions of opposite chiral magnetic states and explores how lattice relaxation and magnetic anisotropy determine their properties.

Findings

SDWs originate from superpositions of opposite chiral states

Lattice relaxation influences the transition from SDW to chiral magnetic states

Type of SDW (transversal or longitudinal) depends on magnetic anisotropy

Abstract

A magnetic solid with weak spin frustration tends to adopt a noncollinear magnetic structure such as cycloidal structure below a certain temperature and a spin density wave (SDW) slightly above this temperature. The causes for these observa-tions were explored by studying the magnetic structures of BaYFeO4, which undergoes an SDW and a cycloidal phase transi-tion below 48 and 36 K, respectively, in terms of density func-tional theory calculations. We show that an SDW structure aris-es from a superposition of two magnetic states of opposite chi-rality, an SDW state precedes a chiral magnetic state due to the lattice relaxation, and whether an SDW is transversal or longitudinal is governed by the magnetic anisotropy of magnetic ions.