Applicability of molecular statics simulation to partial dislocations in GaAs

Abstract

The suitability of empirical potential molecular statics (MS) simulations to provide an approximate structural description of 90° glide set partial dislocation cores in GaAs is analyzed. This is of interest for investigation of the properties of dislocated nanostructures, which are too large for density functional theory simulations. In the MS method the atomic positions are iteratively relaxed by energy minimization, by using a Tersoff potential parametrization appropriate for nanostructures. We show that for the Ga terminated partial the resulting bond lengths of the atoms in the dislocation core agree within 5–10% with those of previous density functional theory studies, whereas a significant discrepancy appears in the case of the As terminated partial.