The effects of hydrostatic pressure upon the formation energy and electronic level positions of cation vacancies in GaN, AlN and GaAs were examined by means of ab initio calculations; using a super-cell approach and the full-potential linear muffin-tin orbital method. Atomic relaxations were taken fully into account. Substantial differences were revealed in the pressure behavior of the defect level positions and the formation energies for cation vacancies in the nitride compounds and in GaAs. In addition, the As antisite in GaAs was examined. This also exhibited a pressure response which was different to that of vacancies. The pressure effect was strong for the vacancy and the antisite in GaAs, but was rather weak for similar defects in the III-V nitrides.

Influence of Hydrostatic Pressure on Cation Vacancies in GaN, AlN and GaAs. I.Gorczyca, N.E.Christensen, A.Svane: Physical Review B, 2002, 66[7], 075210 (5pp)