PLASMA MODES IN PERIODIC 2-DIMENSIONAL SUPERCONDUCTING-WIRE NETWORKS

We have investigated plasma modes in thin niobium superconducting wire networks deposited onto a SrTiO3 substrate and find that their freque ncy is strongly lowered in comparison to homogeneous films. The disper sion relations present a crossover from a thin film regime (two dimens ional) to a wire regime (one dimensional). Surprisingly it occurs at a very long wavelength that is nearly sixty times larger than the array period. A model based on interacting independent parallel wires is pr oposed to understand this crossover. [S0163-1829(98)50638-8].