Magnetic-induced phonon anisotropy in ZnCr$_2$O$_4$ from first principles

TL;DR

This study investigates how magnetic order affects optical phonons in ZnCr₂O₄ using first-principles calculations, introducing a new method to compute spin-phonon coupling from exchange derivatives.

Contribution

The paper presents a novel approach to calculate exchange derivatives and spin-phonon coupling from first-principles, specifically applied to ZnCr₂O₄.

Findings

Magnetic order influences optical phonons in ZnCr₂O₄.

Developed a method to derive spin-phonon coupling from first-principles.

Performed calculations within LSDA+U framework.

Abstract

We have studied the influence of magnetic order on the optical phonons of the geometrically frustrated spinel ZnCr$_2$O$_4$ from first-principles. By mapping the first-principles phonon calculations onto a Heisenberg-like model, we developed a method to calculate exchange derivatives and subsequently the spin-phonon couping parameter from first-principles. All calculations were performed within LSDA+U.