Study of linear and non-linear optical properties of In–Se doped chalcogenide semiconducting glasses

The present work focuses on the various linear and non-linear optical properties of antimony (Sb) and gallium (Ga) (both 0.1 at.%) doped Indium selenide chalcogenide glass semiconductors for optoelectronic applications. The bulk samples were synthesized via the melt quench approach and the films were prepared by the thermal evaporation method from the synthesized bulk. These samples were characterized by XRD and UV–Vis spectroscopy. The optical band-gap of all synthesized films was calculated with the help of Tauc’s plot. The linear refractive index of the synthesized samples was obtained through the transmission spectra using the Swanepoel method. Linear parameters such as absorption coefficient and extinction coefficient were determined using the absorption data. Wemple DiDomenico model was used to calculate parameters oscillator energy (Eo), dispersive energy (Ed), and static refractive index (no). First-order non-linear susceptibility (χ1) has been determined by using the static refractive index in the long-wavelength region. Non-linear index of refraction (n2) and third-order non-linear susceptibility (χ3) is investigated using the Tichy and Ticha relation with the combination of Miller’s generalized rule. Improved non-linearity in antimony doped InSe4 films makes these useful for non-linear optical applications.