Nonlocal effects in the electrodynamics of metallic slabs

The influence of spatial dispersion and size on the interaction of a metallic slab with electromagnetic radiation has been studied in the model of the Boltzmann kinetic equation. It has been shown that the results are qualitatively different from those obtained in the Drude-Lorentz approximation. In particular, in the high-frequency region, the absorption oscillates with the radiation frequency and sample thickness. The absorption becomes sensitive to the Fermi velocity of electrons and depends nontrivially on the electron relaxation rate. The results may be useful for the analysis of the electromagnetic response of metal-dielectric micro- and nanostructures in the terahertz and/or infrared frequency range.