Optical and electronic properties for As-60 at.% S uniform thickness of thin films: Influence of Se content

Thin films of As40S60-xSex ((0 <= x >= 60) at. %) have been efficiently synthesized through the process of vacuum thermal evaporation. The present framework analyzes the thin films to determine both optical and electronic parameters as a function of change of Se concentrations. The thickness of the obtained films, d have been mathematically determined utilizing Swanepoel's computations and experimentally via an MII-4 interference microscope with an accuracy of 1%. The thickness of the studied films has been closed to 500 +/- 15 nm. Additionally, the optical properties of these films have been scrutinized from the transmittance and reflectance spectra measured by a UV-Vis-NIR spectrophotometer. The transmission spectra, T (lambda) of such films have been documented in the spectral region 400-2500 nm. Based on the optical measurements, all of the linear optical constants, the linear optical and dielectric parameters, the linear and non-linear optical susceptibility criteria, and the material dispersion coefficient M(lambda) have been computed. Besides, the nonlinear refractive index, energies of the electronic polarization have been determined.