Effects of dimension on optical transmittance of semicontinuous gold films

The thickness dependence of dielectric response of semicontinuous gold film s evaporated onto glass substrates under various temperatures has been stud ied. A wide range of mass thicknesses (and filling factors) was considered, up to those corresponding to continuous films. The work includes a brief i ntroduction, description of sample preparation and transmittance measuremen ts, as well as determination of the dielectric response function using simp le phenomenological model, namely, the generalized Bruggeman approximation. The approximation considers system's dimension as a varied noninteger quan tity near the percolation threshold where the correlation length is large. The results obtained show that our model is valid in the actual range and d ielectric properties of films are related to their morphological peculiarit ies. So, we refine and supplement some of our results reported in an earlie r work (Proc. SPIE 3133 (1997) 300). (C) 2001 Elsevier Science B.V. All rig hts reserved.