FREQUENCY DEPENDENT EFFECTIVE CONDUCTIVITY OF TWO-DIMENSIONAL METAL–DIELECTRIC COMPOSITES

Abstract

We analyze a random resistor–inductor–capacitor (RLC) lattice model of two-dimensional metal–insulator composites. The results are compared with Bruggeman's and Landauer's Effective Medium Approximations where a discrepancy was observed for some frequency zones. Such a discrepancy is mainly caused by the strong conductivity fluctuations. Indeed, a two-branches distribution is observed for low frequencies. We show also by increasing the system size that at pc the so-called Drude peak vanishes; it increases for vanishing losses.