NONLINEAR ELECTROMAGNETIC PROPERTIES OF FRACTAL METAL-CLUSTERS

We demonstrate that fractal clusters of small metal particles suspende d in a dielectric host have a much larger absorption coefficient in th e far-infrared region. The previous linear result is verified and gene ralized to the non-linear results. As a quasi-analytical model for the non-linear response of fractal clusters, we derive the non-linear dif ferential effective-medium approximation in an attempt to understand t he enhanced non-linear response.