Tetragonal and trigonal deformations in zinc-blende semiconductors: A tight-binding point of view

The deformation potentials of cubic semiconductors are reexamined from the point of view of the extended-basis sp³d⁵s* tight-binding model. Previous parametrizations had failed to account properly for trigonal deformations, even leading to incorrect sign of the acoustic component of the shear deformation potential d. The strain-induced shifts and splittings of the on-site energies of the p and d orbitals are shown to play a prominent role in obtaining satisfactory values of deformation potentials both at the zone center and zone extrema. The present approach results in excellent agreement with available experimental data and recent ab initio calculations.