Transparent and conductive ZnS (32 nm)/Ag (16 nm)/ZnS (32 nm) (ZAZ) sandwich structures are deposited on BK7 substrates by vacuum thermal evaporation. Transparent conductive films have unique characteristics such as low resistivity, high optical transmittance in the visible region and high absorption in the ultraviolet regions. The structure of the films is determined by in situ HT-XRD method. The optical properties of the films are ascertained by UV-VIS spectrophotometer. The refractive index n and the extinction coefficient k are extracted from the results of spectroscopic ellipsometry measurements by utilizing the Cauchy model, the refractive index and effective dielectric function are determined.

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TiO2/X(X = Au and Ag) nanolayers are fabricated by depositing TiO2 films using rf magnetron sputtering on thin quartz substrates embedded with Au and Ag nanoparticles. Enhancement of light absorption of the nanostructural layers is observed. These plasmonic and non-plasmonic materials are ordered in geometric arrangements with dimensions that are fractions of the wavelength of light. The light absorption enhancement of synthesized structure in comparison to TiO2 is originated from near-field enhancement caused by the plasmonic effect of metallic nanoparticles, which can be demonstrated by the optical absorption spectra. We show that plasmon modes can exist for the infrared region of the optical spectrum. Also, we analyze the optical properties of the metalinsulator films, in order to clarify the role of metal inclusions in the TiO2 dielectric matrix. Optical band gaps of the nanolayer films are calculated by using Tauc's relation, and the 𝑛 values of optical band gaps with the variation composition are found from 1.80 to 3.69 eV. Band gap narrowing and absorption in the visible spectral region induced by the incorporation of TiO2/X(X=Au and Ag) nanolayers enable the design of nanostructured thin films to be achieved for photocatalysts and solar energy converters.

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