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.