Tuning magnetism of monolayer GaN by vacancy and nonmagnetic chemical doping

Abstract

In view of important role of inducing and manipulating the magnetism in 2D materials for the development of low-dimensional spintronic devices, the magnetism of GaN monolayer with Ga vacancy and nonmagnetic chemical doping are investigated using first-principles calculations. It is found that pure GaN monolayer has graphene-like structure and is nonmagnetic. While, a neutral Ga vacancy can induce 3μB intrinsic magnetic moment, localized mainly on the neighboring N atoms. Interestingly, after one Mg or Si atom doping in g-GaN with Ga vacancy, the magnetic moment can be modified to 4μB or 2μB respectively due to the change in hole number. Meantime, Mg-doped g-GaN with Ga vacancy shows half-metal character. With the increasing of doping concentrations, the magnetic moment can be further tuned. The results are interesting from a theoretical point of view and may open opportunities for these 2D GaN based materials in magnetic devices.