Forward Raman scattering in GaAs/AlAs superlattices: Study of optical phonon anisotropy

We present the forward Raman scattering study of zone-centre optical phonon anisotropy in short-period GaAs/AlAs superlattices. Experiments were performed on specially prepared superlattice structures having anti-reflection dielectric coatings and removed substrates. The experimental data are compared with the angular dispersion of superlattice optical phonons calculated within the dielectric susceptibility model. We have found a good agreement between the experimental data and the calculations taking into account interface disorder