Calculations were made of the absolute formation energies of native defects in this compound. It was found that the formation energy, and thus the equilibrium concentration of the defects, depended strongly upon the atomic chemical potentials of As and Ga, as well as upon the electron chemical potential. Hence, the Ga vacancy concentration changed by more than 10 orders of magnitude as the chemical potentials of As and Ga varied between the thermodynamically allowed limits. It was deduced that the rate of self-diffusion depended markedly upon the surface annealing conditions.

S.B.Zhang, J.E.Northrup: Physical Review Letters, 1991, 67[17], 2339-42