Electronic origin of spin-phonon coupling effect in transition-metal perovskites

TL;DR

This paper investigates the electronic origins of spin-phonon coupling in transition-metal perovskites using first-principles calculations and a Wannier-based model, highlighting the importance of electron orbitals and configurations.

Contribution

It introduces a Wannier-based extended Kugel-Khomskii model to analyze spin-phonon coupling, successfully applied to SrMnO₃ and BiFeO₃, emphasizing electronic factors.

Findings

Electronic structure influences spin-phonon coupling variances.

Both electron orbitals and configurations are crucial.

The approach explains differences among phonon modes and materials.

Abstract

By applying Wannier-based extended Kugel-Khomskii model, we carry out first-principles calculations and electronic structure analysis to understand the spin-phonon coupling effect in transition-metal perovskites. We demonstrate the successful application of our approach to SrMnO$_3$ and BiFeO$_3$. We show that both the electron orbitals under crystal field splitting and the electronic configuration should be taken into account in order to understand the large variances of spin-phonon coupling effects among various phonon modes as well as in different materials.