Theory of point defects in GaN, AlN, and BN: Relaxation and pressure effects

Native defects and some common dopants in cubic GaN, AlN, and BN are examined by means of ab initio calculations using a supercell approach in connection with the full potential linear muffin-tin orbital method. The atomic positions, the electronic structure, and the defect formation energies are calculated. In particular, the vacancies are calculated to be abundant defects. The high-pressure behavior of the defect states is also studied, and it is found that the pressure coefficients of the defect states depend mainly on their position in the energy gap.