The role of Coulomb and exchange interaction on the Dzyaloshinskii-Moriya interaction(DMI) in BiFeO3

TL;DR

This study uses ab initio calculations to explore how Coulomb and exchange interactions influence the Dzyaloshinskii-Moriya interaction in BiFeO3, revealing its reduction and eventual destruction with increasing U.

Contribution

It provides a new understanding of how Coulomb interactions affect DMI in BiFeO3, supported by a simple explanatory model.

Findings

DMI decreases as U increases from 0 to 2.9 eV

DMI is destroyed when U exceeds 2.9 eV

Magnetization rotation correlates with antiferrodistortive distortions

Abstract

Ab initio calculations show that the Dzyaloshinskii-Moriya interaction(DMI)and net magnetization per unit cell in BiFeO3 are reduced when U is increasing from 0 to 2.9 eV, and independent of $J$. Interestingly, the DMI is even destroyed as $U$ exceeds a critical value of 2.9 eV. We propose a simple model to explain this phenomenon and present the nature of the rotation of the magnetization corresponding to altered antiferrodistortive distortions under DMI in BiFeO3.