Optical properties of two-dimensional disordered systems on a substrate

We calculate the dielectric response of free-standing and supported two-dimensional layers of polarizable entities, such as metallic particles or adsorbed molecules. We take into account dipole-dipole and the image interaction and investigate the effects of disorder within a two-dimensional renormalized polarizability theory. The behavior of the resonances arising from both the single particle's and the substrate's surface plasmon is studied.