Charge-dependent migration pathways for the Ga vacancy in GaAs

摘要: Using a combination of the local-basis ab initio program SIESTA and activation-relaxation technique we study diffusion mechanisms gallium vacancy in $\mathrm{GaAs}$. Vacancies are found to diffuse second neighbor using two different mechanisms, as well first fourth neighbors following various mechanisms. We find that height energy barrier is sensitive Fermi level generally increases with charge state. Migration pathways themselves can be strongly dependent may appear or disappear function These differences transition state migration explained by transfer takes place during migration.