13 October 1986 New Phenomenological Approach For The Optical Dielectric Function Of Inhomogeneous Media Near The Percolation
Author Affiliations +
Proceedings Volume 0652, Thin Film Technologies II; (1986) https://doi.org/10.1117/12.938376
Event: 1986 International Symposium/Innsbruck, 1986, Innsbruck, Austria
Abstract
The Mean Field Theories developped for the dielectric function of inhomogeneous media (metallic clusters in dielectrics), do not give a proper account of the optical properties for metal volume fractions around the percolation critical fraction. We present a new phenomenological derivation of the Bruggeman formulation valid in the near and middle infrared near the percolation. We first separate the different contributions to the dielectric function in the Bruggeman expression and point out their physical meaning, below and beyond percolation. We show that the conduction and the static dielectric function are predicted to follow scaling laws with an exponent equal to 1. This value does not agree with the critical exponents (s and t) deduced from Monte Carlo simulations and renormalization calculations. A new formulation is proposed by replacing the exponents 1 by their proper values. This formulation is successfully applied to our results on the optical properties of Au-Mg0 and Pt-Al203 cermet thin films.
© (1986) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
J Lafait, S Berthier, L E Regalado, "New Phenomenological Approach For The Optical Dielectric Function Of Inhomogeneous Media Near The Percolation", Proc. SPIE 0652, Thin Film Technologies II, (13 October 1986); doi: 10.1117/12.938376; https://doi.org/10.1117/12.938376
PROCEEDINGS
8 PAGES


SHARE
Back to Top