%0 Journal Article
%T Self-vacancies in gallium arsenide: An ab initio calculation
%V 71
%N 12
%P 125207
%U http://link.aps.org/doi/10.1103/PhysRevB.71.125207
%X We report here a reexamination of the static properties of vacancies in GaAs by means of first-principles density-functional calculations using localized basis sets. Our calculated formation energies yields results that are in good agreement with recent experimental and ab initio calculation and provide a complete description of the relaxation geometry and energetic for various charge states of vacancies from both sublattices. Gallium vacancies are stable in the 0, −, −2, −3 charge states, but V−3Ga remains the dominant charge state for intrinsic and n-type GaAs, confirming results from positron annihilation. Interestingly, arsenic vacancies show two successive negative-U transitions making only +1, −1, and −3 charge states stable, while the intermediate defects are metastable. The second transition (−/−3) brings a resonant bond relaxation for V−3As similar to the one identified for silicon and GaAs divacancies.
%J Physical Review B
%A El-Mellouhi, Fedwa
%A Mousseau, Normand
%D March 18, 2005