“Effects of Interfacial Layer on Refractive Index and Propagation of Waves in Small Spherical Metal/Dielectric Composites”

Abstract

The increasing interest in optical properties of the composite media is dictated by the fact that small particles, which are randomly embedded in a linear dielectric host matrix, can be manufactured with the help of modern technology with desirable properties[1]. It is known that the particles with metal covering can considerably enhance the refractive index of the incident electromagnetic waves and reduce the group velocity if their frequency approaches to the frequency of the metal surface plasmon’s[2]. In this work in comparison with no interfacial layer factor we have shown the effects of interfacial layer on the refractive index, and propagation of waves in metal/dielectric composite separated by interfacial layers which is randomly embedded in a linear dielectric host matrix. The corresponding theoretical, and numerical descriptions are in terms of the interfacial factor (I ) by making use of the Drude model. Finally, both the interfacial layer property and the percentage of the volume fraction of the metallic particles in the composite has a nonlinear optical response which strongly effect on the refractive index, and propagation of waves of the composite when the dielectric functions of the interfacial layer is more metal-like property than dielectric-like property.