Interface-phonon dispersion and confined-optical-mode selection rules of GaAs/AlAs superlattices studied by micro-Raman spectroscopy

Using micro-Raman spectroscopy, we study backscattering from (010) and (11{}0) surfaces of [001]-grown superlattices and establish experimental selection rules. By changing the momentum transfer q_∥ parallel to the superlattice layers over a wide range (0{≤}q_∥{≤}9×{}10⁵ cm^-1), we studied the dispersion of the interface phonons. The measured dispersion curves are compared to calculations based on the dielectric-continuum model.