Strain engineering multiferroism in Pnma NaMnF3 fluoroperovskite

TL;DR

This paper demonstrates through first principles calculations that epitaxial strain can induce multiferroic and magnetoelectric properties in NaMnF3 fluoroperovskite, revealing strong polarization-strain coupling and potential for functional applications.

Contribution

It introduces a novel approach of strain engineering to induce multiferroism in NaMnF3, highlighting atypical polarization amplification and magnetoelectric responses.

Findings

Strong non-linear polarization-strain coupling observed.

Induction of multiferroic behavior via strain in NaMnF3.

Magnetoelectric response comparable to Cr2O3.

Abstract

In this study we show from first principles calculations the possibility to induce multiferroic and magnetoelectric functional properties in the Pnma NaMnF3 fluoroperovskite by means of epitaxial strain engineering. Surprisingly, we found a very strong non-linear polarization-strain coupling that drives an atypical amplification of the ferroelectric polarization for either compression or expansion of the cell. This property is associated with a non-collinear antiferromagnetic ordering, which induces a weak ferromagnetism and thus, making the strained NaMnF3 fluoroperovskite multiferroic. We also calculate the magnetoelectric response and we found it to be composed by linear and non-linear components with amplitudes similar to the ones of Cr2O3. These properties show that it is possible to move the fluoride family toward functional applications with unique responses.