Abstract
The changes brought about by the annealing in the optical properties forms the basis of optical storage technique. Considering this, the effect of annealing on as-prepared (Dy) doped (GeSe2)(80)(Sb2Se3)(20) thin films in optical properties has been studied in the current study. The refractive index (n) and thickness (d) of the thin films have been calculated from the transmission spectra. It is noticed that the absorption coefficient (alpha) decreases with annealing temperature. The values of alpha have further been used to calculate the optical band gap using the Tauc relation. The oscillator parameters have been calculated using the models proposed by Wemple DiDomenico (WDD) and Sellmeier. From the dispersion of n(2), the ratio N/m* has been determined which gives an idea about the free carrier concentration. Electric modulus analysis shows the presence of relaxation processes in the thin films. Annealing increases the transmission range of as-prepared film and modifies its optical parameters, which motivates the exploration of the studied system for applications in IR region.