Microscopic parameters of the van der Waals CrSBr antiferromagnet from microwave absorption experiments

TL;DR

This study uses microwave absorption experiments to analyze the magnetic resonance modes of CrSBr, a van der Waals antiferromagnet, revealing anisotropies and enabling precise determination of microscopic magnetic parameters.

Contribution

The paper introduces a microscopic spin model with bi-axial anisotropy and inter-plane exchange that accurately describes the magnon spectra of CrSBr.

Findings

Identification of anisotropic magnetic resonance modes

Precise determination of microscopic interaction parameters

Excellent agreement between theory and experiment

Abstract

Microwave absorption experiments employing a phase-sensitive external resistive detection are performed for a topical van der Waals antiferromagnet CrSBr. The field dependence of two resonance modes is measured in an applied field parallel to the three principal crystallographic directions, revealing anisotropies and magnetic transitions in this material. To account for the observed results, we formulate a microscopic spin model with a bi-axial single-ion anisotropy and inter-plane exchange. Theoretical calculations give an excellent description of full magnon spectra enabling us to precisely determine microscopic interaction parameters for CrSBr.