Isoelectronic substitutional impurity-induced optical absorption in an NaCl-type semiconductor

摘要

The structures in the complex dielectric function of an isoelectronic substitutional dilute alloy have been analysed in terms of extra and missing wavevector conserving transitions. Wavevector non-conserving transitions have not been pointed out for an s conduction band and a p valence band with NaCl structure. The transitions are related to the modification of the host density of states due to the impurity potential. The lowest-energy direct transitions give rise to a structure which can be used to determine or to confirm the band gap energy. The other transitions serve to investigate critical points in the Brillouin zone.