Effects of Nitrogen Defect on Magnetism of Cu-doped InN: First-principles Calculations

We investigate the electronic and magnetic properties in Cu-doped InN with the N vacancy (VN) from first principles calculations. There is the long-range ferromagnetic order between two Cu atoms, attributed to the hole-mediated double exchange through the strong p-d interaction between the Cu atom and neighboring N atom. The system of VN defect in Cu-doped InN has the lowest formation energy. Due to the hybridization between the Cu-3d and VN states, the spin-polarization on the Cu atoms in the InN lattice is reduced by VN defect. So, it shows a weak ferromagnetic behavior.