Migration barriers of neutral As di-interstitials in GaAs

The recent discovery of intrinsic di-interstitial stability against the isolated self-interstitial point defects in GaAs has evidenced the importance of such complexes in, for instance, irradiated GaAs. In this paper, we illustrate and discuss diffusion of such complexes in comparison with isolated self-interstitials. In particular, the diffusion barriers of neutral di-interstitials have been calculated in the framework of density functional theory, showing that, in addition to their being stable, di-interstitials can also diffuse rapidly through the lattice, similarly to isolated self-interstitials.