Surface waves in plasmonic anisotropie media

We investigate the spatial dispersion of hybrid-polarized surface waves excited at the boundary of a semi-infinite layered metal-dielectric nanostructure. We put emphasis in the case that the thickness of a metal layer becomes of the order of the metal skin depth. We demonstrate that the use of the so-called effective medium approximation (EMA) is not justified, in general. For that purpose, we compare the results using the EMA model and numerical simulations based on the finite-element method. We include an analysis of the influence of metallic losses.