Light Scattering from Quantum Confined and Interface Optical Vibrational Modes in Strained-Layer GaSb/AlSb Superlattices.
01 January 1987
Raman scattering has been performed on GaSb/AlSb strained- layer superlattices with periods varying from 65 to 300angstroms. Discrete quantum confined GaSb longitudinal optical phonons are observed in GaSb layers less than 25angstroms thick. The confinement-induced GAMMA to L crossover in GaSb manifests itself in our spectra via the observation of optical phonon density of states structure. This structure disappears for GaSb layers thicker than 50angstroms . Spatially extended interface modes have been observed in all superlattices in both the GaSb and AlSb optical mode spectra.