Experimental study of Cu–PbCl_2, Cu–NaF, Ag–PbCl_2, and Ag–NaF cermet thin films

Abstract
We present in this paper the experimental spectral transmission curves of four different cermets, Cu–PbCl2, Cu–NaF, Ag–PbCl2, and Ag–NaF, as well as the calculated curves obtained from the generalized Maxwell-Garnett theory. The results show that the microstructure of the metal particles in the dielectric matrix is independent of the nature of the dielectric. We also show that this behavior is predicted by the generalized Maxwell-Garnett theory. However, our measurements also indicate that the microstructure is the same for both copper and silver cermets. This last experimental evidence cannot be explained within the context of the Maxwell-Garnett theory.