Electronic and magnetic properties of single-layer MPX3 metal phosphorous trichalcogenides

We survey the electronic structure and magnetic properties of two-dimensional (2D) MPX3 (M=V,Cr,Mn,Fe,Co,Ni,Cu,Zn, and X=S,Se,Te) transition-metal chalcogenophosphates to shed light on their potential role as single-layer van der Waals materials that possess magnetic order. Our ab initio calculations predict that most of these single-layer materials are antiferromagnetic semiconductors. The band gaps of the antiferromagnetic states decrease as the atomic number of the chalcogen atom increases (from S to Se to Te), leading in some cases to half-metallic ferromagnetic states or to nonmagnetic metallic states. We find that the competition between antiferromagnetic and ferromagnetic states can be substantially influenced by gating and by strain engineering. The sensitive interdependence we find between magnetic, structural, and electronic properties establishes the potential of this 2D materials class for applications in spintronics.