Ground State of the Quasi-1D \bvs\ resolved by Resonant Magnetic X-ray Scattering

TL;DR

This study uses resonant magnetic x-ray scattering to determine the low-temperature magnetic structure of high-quality vs\ crystals, revealing a triple-incommensurate antiferromagnetic order below 31 K with spins aligned along the a-axis.

Contribution

First application of RMXS to vs\, identifying its incommensurate magnetic order and spin polarization direction through combined experimental and theoretical analysis.

Findings

Magnetic order appears below 31 K with wave vector (0.226 0.226 0.033).

RMXS spectra match simulations indicating antiferromagnetic order.

Spins are polarized along the a-axis in the monoclinic structure.

Abstract

Resonant-magnetic x-ray scattering (RMXS) near the vanadium $L_{2,3}$-absorption edges has been used to investigate the low temperature magnetic structure of high quality \bvs\ single crystals. Below $T_N$ = 31 K, the strong resonance revealed a triple-incommensurate magnetic ordering at wave vector (0.226 0.226 $\xi$) in the hexagonal notation, with $\xi$ = 0.033. The simulations of the experimental RMXS spectra with a time-dependent density functional theory indicate an antiferromagnetic order with the spins polarized along $a$ in the monoclinic structure.