Optical properties of random metal-dielectric nanocomposite films: nanoparticle size effects

The optical properties of a semicontinuous metal film that contains randomly distributed dielectric nanoparticles are analyzed by taking into account both filling ratios and nanoparticle size effects. A new generalization of the standard Maxwell-Garnett formula for the present system is derived, by means of the linearized hydrodynamic theory in conjunction with the Poisson equation and the appropriate boundary conditions. The dispersion curves of surface modes of the system are presented and found to be strongly dependent on the volume fraction of particles as well as the particles size. The attenuated total reflection spectra due to surface modes for the case of p-polarization are plotted and the effect of varying filling factor for fixed nanoparticles size is studied, as well as the effect of varying nanoinclusions size for a fixed volume fraction of particles.