ELECTRON-ENERGY-LOSS SPECTRUM OF THE CUPRATE SUPERCONDUCTORS

We present a theoretical description of the near-specular (dipole) electron-energy-loss spectrum of a superlattice constructed from anisotropic dielectric layers, as a model of the superconducting copper-oxide-based materials. The theory is applied to a description of recent data taken on the Bi 2:2:1:2 compound. We find that parameters deduced from the electron loss spectrum are compatible with infrared reflectivity data. Manifestations of the superconducting energy gap are not evident in the new data.