Dynamical strain at semiconductor interfaces: Structure and surface-atom vibrations of GaAs(110) and GaAs(110)–p(1×1)–Sb

Abstract

The dynamical force fields of the clean GaAs(110) surface, an isolated Sb chain, and the GaAs(110)–p(1×1)–Sb(1‐ML) interface have been computed utilizing tight‐binding total energy models that have been used successfully to describe the atomic and electronic structure of the clean and adsorbed cleavage faces of the tetrahedrally coordinated compound semiconductors. Since the main consequences of the different chemical bonding in these two cases are manifested in changes in the force field associated with the dynamics of the top‐layer atoms, we explore these consequences using a restricted dynamical model in which only the top‐layer atoms are allowed to vibrate. The resulting vibrational energies are in remarkably good agreement with experimental measurements, and hence afford a vehicle to obtain quantitative relationships between the nature of the surface chemical bonds and the vibrational energies of the surface atomic species.