Orthorhombic $ABC$ semiconductors as antiferroelectrics

TL;DR

This paper identifies a new class of antiferroelectric materials within orthorhombic $ABC$ semiconductors using first-principles calculations, highlighting their potential for practical applications.

Contribution

It uncovers a previously unrecognized class of antiferroelectric materials in the MgSrSi structure type and analyzes their energetic proximity to related polar and nonpolar structures.

Findings

Many $ABC$ compounds are close in energy to polar structures.

Some compounds have energy barriers comparable to known antiferroelectrics.

Structural parameters for both known and hypothetical compounds are provided.

Abstract

We use a first-principles rational-design approach to identify a previously-unrecognized class of antiferroelectric materials in the $Pnma$ MgSrSi structure type. The MgSrSi structure type can be described in terms of antipolar distortions of the nonpolar $P6_{3}/mmc$ ZrBeSi structure type, and we find many members of this structure type are close in energy to the related polar $P6_{3}mc$ LiGaGe structure type, which includes many members we predict to be ferroelectric. We highlight known $ABC$ combinations in which this energy difference is comparable to the antiferroelectric-ferroelectric switching barrier of PbZrO$_{3}$. We calculate structural parameters and relative energies for all three structure types, both for reported and as-yet hypothetical representatives of this class. Our results provide guidance for the experimental realization and further investigation of high-performance materials suitable for practical applications.