Intrinsic triferroicity in a two-dimensional lattice

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 the basis of first principles, we report the intrinsic triferroicity in a 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 degrees 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.

Automated summary

In this study, intrinsic triferroicity was demonstrated in a two-dimensional lattice, with single-layer FeO2H shown to exhibit antiferromagnetism, ferroelasticity, ferroelectricity, and in-plane piezoelectric effect. These findings not only expand the scientific and technological impact of triferroics but also open up a wide range of nanodevice applications.