Using density functional theory, we study the magnetic stability of the
Ga1βxβMnxβN alloy system. We show that unlike Ga1βxβMnxβAs, which
shows only ferromagnetic (FM) phase, Ga1βxβMnxβN can be stable in either
FM or antiferromagnetic phases depending on the alloy concentration. The
magnetic order can also be altered by applying pressure or with charge
compensation. A unified model is used to explain these behaviors.Comment: 4 pages, 4 figure