Planar vibrational modes as probes of interface structure

Abstract
Raman-scattering studies are reported for a vibrational mode with an eigenvector localized at planes of interface atoms of heterojunctions. These planar vibrational modes (PVM’s) are studied in a variety of structures formed in the III-V 6.1-Å semiconductor materials family of GaSb, InAs, and AlSb with interface planes involving GaAs or AlAs bonds. The results of these measurements are compared with calculations of the eigenvectors and eigenenergies of the PVM’s and are related to a simple one-dimensional model that describes the segregation of atoms during growth.