Acoustic deformation potentials and heterostructure band offsets in semiconductors

It is argued that the absolute hydrostatic deformation potentials recently calculated for tetrahedral semiconductors with the linear muffin-tin-orbital method must be screened by the dielectric response of the material before using them to calculate electron-phonon interaction. This screening can be estimated by using the midpoint of an average dielectric gap evaluated at special (Baldereschi) points of the band structure. This dielectric midgap energy (DME) is related to the charge-neutrality point introduced by Tejedor and Flores, and also by Tersoff, to evaluate band offsets in heterojunctions and Schottky-barrier heights. We tabulate band offsets obtained with this method for several heterojunctions and compare them with other experimental and theoretical results. The DME’s are tabulated and compared with those of Tersoff’s charge-neutrality points.