Computational design of a robust two-dimensional antiferromagnetic semiconductor

Using density functional theory calculations, we establish the hitherto unknown compound CrCTe3 to be a stable antiferromagnetic semiconductor in the R3 crystal structure with an indirect fundamental gap. Successive layers in the bulk compound are weakly bound by van der Waals forces so that individual layers can be easily exfoliated. A monolayer of CrCTe3 is also an antiferromagnetic semiconductor. The monolayer is structurally stable over a large range of compressive and tensile strains, and the antiferromagnetic state is robust over this strain range. Band gap of the monolayer can be tuned by as much as 50% by applying strain in this range.