PHENOMENOLOGICAL ELECTRODYNAMICS OF ELECTRONIC SUPERLATTICES

We set up the phenomenological electrodynamics and establish the gener alized dispersion relation for a model type-I superlattice. The presen ce of a constant externally applied magnetic field is assumed. Field e quations and the fluctuation-dissipation theorem are formulated exclus ively in terms of Fourier-transformed monolayer source and field quant ities. The significance of the correct dispersion relation is especial ly striking when applied to the calculation of the eigenfrequencies of the slow transverse modes (such as the helicon).