PLASMONS IN DOPED SEMICONDUCTOR SUPERLATTICE WITH CHARGE DEPLETION AND A CAPPING LAYER

We present a theoretical analysis for the collective plasmon-polariton modes of a doped superlattice consisting of two-dimensional electron gas and two-dimensional hole gas layers separated by media of alternating thickness and dielectric constant. Our theory takes into account the effects due to a capping layer, as well as charge depletion near the superlattice surface. We use a theoretical model based on linear response function together with a transfer matrix approach to determine the plasmons dispersion relation and Green functions. Numerical applications are made to semiconductor superlattices, with interesting features for the plasmon surface modes.