First-principle Studies on Ferromagnetism of Fe-doped AlN Diluted Magnetic Semiconductors

We have studied the electronic structures and magnetic properties of Fe-doped AlN by first-principles calculations within density functional theory. The calculated results show that AlN crystals doped by double Fe atoms display ferromagnetic properties, and the total magnetic moment is 10.0 μB per 72-atom supercell (3 × 3 × 2). The calculated energy differences between the antiferromagnetic (AFM) and ferromagnetic (FM) phases are 207 meV, which means FM state is a stable state. It is also found that the 3d-states of Fe dopants and the 2p-states of N atoms bonding to Fe dopants are the main contributors to the density of states at the Fermi level