Prediction of Intrinsic Triferroicity in Two-Dimensional Lattice

TL;DR

This paper predicts intrinsic triferroicity in a two-dimensional material, FeO2H, exhibiting antiferromagnetism, ferroelasticity, and ferroelectricity, with potential for advanced nanodevices.

Contribution

It demonstrates for the first time the existence of intrinsic triferroicity in a 2D lattice based on first-principles calculations.

Findings

Single-layer FeO2H is an intrinsically triferroic semiconductor.

FeO2H exhibits reversible ferroelastic switching controlling ferroelectric polarization.

The material also shows in-plane piezoelectric effects.

Abstract

Intrinsic triferroicity is essential and highly sought for novel device applications, such as high-density multistate data storage. So far, the intrinsic triferroicity has only been discussed in three-dimensional systems. Herein on basis of first-principles, we report the intrinsic triferroicity in two-dimensional lattice. Being exfoliatable from the layered bulk, single-layer FeO2H is shown to be an intrinsically triferroic semiconductor, presenting antiferromagnetism, ferroelasticity and ferroelectricity simultaneously. Moreover, the directional control of its ferroelectric polarization is achievable by 90{\deg} reversible ferroelastic switching. In addition, single-layer FeO2H is identified to harbor in-plane piezoelectric effect. The unveiled phenomena and mechanism of triferroics in this two-dimensional system not only broaden the scientific and technological impact of triferroics but also enable a wide range of nanodevice applications.