Prediction of Room Temperature Electric Field Reversal of Magnetization in the Family of $A_4B_3\rm{O}_9$ Layered Oxides

TL;DR

This study predicts a new polar phase in $A_4B_3O_9$ layered oxides enabling electric field-induced magnetization reversal at room temperature, highlighting their potential for advanced memory devices.

Contribution

The paper introduces a previously unknown polar phase in $A_4B_3O_9$ oxides with a unique magnetoelectric coupling allowing electric control of magnetization.

Findings

Identification of a new polar phase in $A_4B_3O_9$ oxides

Room temperature magnetism predicted in these compounds

Magnetization can be reversed by electric field switching

Abstract

The promise of a strong magnetoelectric coupling in a multiferroic material is not only of fundamental interest, but also forms the basis of next generation memory devices where the direction of magnetization can be reversed by an external electric field. Using group-theory led first-principles calculations, we have identified a hitherto unknown polar phase of the $A_4B_3\rm{O}_9$ layered oxides, where the polar mode couples to the magnetic modes through a rare $\Gamma$-point magnetoelectric-multiferroic coupling scheme such that the net magnetization can be directly reversed by an electric field switching of the polar mode. Furthermore, in agreement with previous experimental observations, we predict room temperature magnetism in $A_4B_3\rm{O}_9$ oxides which indicates the promising practical applications of these compounds in the next generation memory devices.