Development of a Gaussian Approximation Potential for Gan With Point Defects and Mg Impurities

Abstract

We present a new Gaussian approximation potential (GAP) for the Ga-N-Mg system, developed to accurately describe GaN containing point defects and Mg impurities. By carefully sampling a diverse set of defect-containing and doped structures, the potential reproduces the formation energies and diffusion barriers of point defects in GaN as calculated by density functional theory. Specifically, the GAP reproduces formation energies within a maximum deviation of 1.9 eV and diffusion barrier energies within 0.4 eV. This potential enables large-scale molecular dynamics simulations of defect dynamics in GaN, including the effects of Mg doping.