Optical properties and collective excitations of plasmons in semiconductor superlattices in magnetic fields

Using the random-phase approximation the density-density correlation function including intra- and inter-Landau level transitions in a finite type-I superlattice is obtained under magnetic fields parallel to interfaces on the basis of a simple model of parabolic confining potentials. The dispersion relation for surface and bulk states is investigated according to the strength of magnetic field, the momentum wave vector, and the ratio of the confining potential parameter to cyclotron resonance frequency. The Raman intensities and their shifts for the bulk and surface plasmons are also examined according to the strength of magnetic field and the momentum wave vector in the presence and the absence of magnetic field.