ANISOTROPY OF OPTICAL PHONONS IN SEMICONDUCTOR SUPERLATTICES - RAMAN-SCATTERING EXPERIMENTS

Experiments on Raman scattering in the ''forward'' geometry, permit ti ng observation of anisotropy of the optical phonons, are performed on specially prepared short-period GaAs/AlAs superlattice structures with the substrates removed and the surfaces covered with an antireflectiv e layer. The experimental data agree well with the computational resul ts obtained for the angular dispersion of optical phonons in superlatt ices on the basis of a modified continuum model. (C) 1998 American Ins titute of Physics.