EFFECT OF A CHARGE LAYER ON THE PLASMON-POLARITON DISPERSION CURVE IN DOPED SEMICONDUCTOR SUPERLATTICES

We consider the effects of a charge layer (accumulation and depletion layers) on the spectrum of collective plasmon-polariton modes of a semiconductor superlattice consisting of alternating media A and B, where medium A is a n-doped semiconductor and medium B an insulator. The effect of the charge layer is taken into account assuming a linear position dependence for the free-carrier concentration and for the dielectric function, within medium A. Applications are made considering medium A as n-type semiconductor and medium B being vacuum. We compare our results with those obtained in the abscence of the charge layer and we discuss their differences. © 1990 Springer-Verlag.