Folded phonons in (GaAs)n1(AlAs)n2superlattices grown along the [012] direction

Abstract

We present Raman scattering data for folded acoustic phonons in GaAs/AlAs superlattices grown along the [012] direction. Doublets of mixed transverse and longitudinal character, with the selection rules predicted by symmetry, are clearly observed. The frequencies of the observed modes are not fully in agreement with calculations based on the continuum model.