Magneto-electric coupling in type-I multiferroic ScFeO$_3$

TL;DR

This study uses ab-initio calculations to explore the electronic structure and ferroelectric properties of ScFeO$_3$, revealing significant magnetoelectric coupling and a large ferroelectric polarization driven by Sc off-centering.

Contribution

It provides the first detailed theoretical analysis of the electronic and ferroelectric properties of ScFeO$_3$, highlighting its strong magnetoelectric interaction in a type-I multiferroic.

Findings

Antiferromagnetic ordering with Néel temperature matching experiments

Large ferroelectric polarization (~105 μC/cm²) driven by Sc off-centering

Ferroelectric polarization is sensitive to Fe magnetic moments

Abstract

We investigate the electronic structure and the ferroelectric properties of the recently discovered multiferroic ScFeO$_3$ by means of ab-initio calculations. The $3d$ manifold of Fe in the half-filled configuration naturally favors an antiferromagnetic ordering, with a theoretical estimate of the antiferromagnetic N\'eel temperature in good agreement with the experimental values. We find that the inversion symmetry-breaking is driven by the off-centering of Sc atoms, which results in a large ferroelectric polarization of $\sim$105\,$\mu$C/cm$^{2}$. Surprisingly the ferroelectric polarization is sensitive to the local magnetization of the Fe atoms resulting in a large negative magnetoelectric interaction. This behavior is unexpected in type-I multiferroic materials because the magnetic and ferroelectric orders are of different origins.