Orbital order and spin-orbit coupling in BaVS3

TL;DR

This paper investigates the complex interplay of orbital order and spin-orbit coupling in BaVS3, revealing how these factors influence its magnetic properties and phase transitions.

Contribution

It introduces a microscopic model incorporating spin-orbit coupling and classifies order parameters, advancing understanding of orbital and magnetic phenomena in BaVS3.

Findings

Orbital ordering affects magnetic susceptibility anisotropy.

Spin-orbit coupling induces mixed spin-orbital character in d-electron multipoles.

Sequence of symmetry-breaking transitions observed in magnetic properties.

Abstract

The correlated 3d sulphide BaVS3 undergoes a sequence of three symmetry breaking transitions which are reflected in the temperature dependence of the magnetic susceptibility, and its anisotropy. We introduce a microscopic model based on the coexistence of wide band a(1g) and localized e(g) d-electrons, and give the classification of the order parameters under the double space group and time reversal symmetries. Allowing for the relativistic spin-orbit coupling, the d-shell multipoles acquire a mixed spin-orbital character. It follows that orbital ordering is accompanied by a change in the susceptibility anisotropy