Electric control of the magnetization in BiFeO$_3$/LaFeO$_3$ superlattices

TL;DR

This study uses first-principles calculations to explore how electric fields can control magnetization in BiFeO3/LaFeO3 superlattices, revealing their potential for room-temperature electric switching of magnetic states.

Contribution

It demonstrates the microscopic mechanism enabling electric control of magnetization in BiFeO3/LaFeO3 superlattices and discusses effects of strain and chemical substitution.

Findings

Superlattices have a Pmc2_1 ground state with coupled polar and rotational modes.

Weak ferromagnetism can be manipulated by electric fields.

Potential for room-temperature electric switching of magnetization.

Abstract

First-principles techniques are used to investigate the behavior of BiFeO$_{3}$/LaFeO$_{3}$ perovskite oxide superlattices epitaxially grown on a (001)-SrTiO$_3$ substrate. The calculations show that 1/1 superlattices exhibit a $Pmc2_1$ ground state combining a trilinear coupling of one polar and two oxygen rotational lattice modes, and weak ferromagnetism. The microscopic mechanism allowing one to manipulate the magnetization with an electric field in such systems is presented and its dependence on strain and chemical substitution is discussed. BiFeO$_{3}$/LaFeO$_{3}$ artificial superlattices appear to be good candidates to achieve electric switching of magnetization at room temperature.