Density-wave propagation within layered high-temperature superconducting plasmas

In the present work we theoretically investigate density-wave propagation i n a superconducting medium, consisting of a finite number of layers. An ele ctromagnetic wave interacts with superconducting electrons to set up charge -density gradients within the superconducting electron plasma. We use the L ondon equations and a two fluid approach along with a Kronig-Penney model t o describe the layered medium, in order to investigate the density wave beh aviour by deriving a linear dispersion relation. It is shown that the charg e density wave dissipates gradually. We numerically investigate the depende nce of the complex Bloch-wave number on the propagation frequency using the standard boundary conditions of the Konig-Penney model. Expressions of ref lectivity and transmissivity are derived for a periodic layered structure c onsisting of a finite number of superconducting layers; these quantities ar e investigated numerically for a high temperature superconductor and their dependence on background parameters is discussed.