Exchange bias driven by the Dzyaloshinskii-Moriya interaction and ferroelectric polarization at G-type antiferromagnetic perovskite interfaces

TL;DR

This paper proposes intrinsic mechanisms involving Dzyaloshinskii-Moriya interaction and ferroelectric polarization to explain exchange bias at G-type antiferromagnetic perovskite interfaces, especially in multiferroic materials, controllable by electric fields.

Contribution

It introduces two intrinsic mechanisms for exchange bias in compensated antiferromagnets, expanding understanding beyond extrinsic factors like interface roughness.

Findings

Mechanisms driven by Dzyaloshinskii-Moriya interaction and ferroelectric polarization are proposed.

One mechanism is controllable by electric fields in multiferroic materials.

Provides alternative explanation for exchange bias in compensated antiferromagnetic interfaces.

Abstract

Exchange bias is usually rationalized invoking spin pinning effects caused by uncompensated antiferromagnetic interfaces. However, for compensated antiferromagnets other extrinsic factors, such as interface roughness or spin canting, have to be considered to produce a small uncompensation. As an alternative, here we propose two (related) possible mechanisms, driven by the intrinsic Dzyaloshinskii-Moriya interaction and ferroelectric polarization, for the explanation of exchange bias effects in perovskites with compensated G-type antiferromagnetism. One of the mechanisms is only active when a multiferroic material is involved and it is controllable by electric fields.