Investigation on Bi-induced changes on linear and non-linear optical parameters of As45-Se (55-x)-Bix chalcogenide glasses for photonic application

Abstract

The Bi-incorporated As45-Se(55-x)-Bix (x = 0, 2, 4, 6 at.%) chalcogenide glasses have been synthesized by deploying the conventional melt quenching method. The non-appearance of the peak in the X-ray diffraction pattern confirms the amorphous characteristics of these materials. The alteration in non-linear and linear optical properties has been investigated from UV–Vis spectroscopy data and associated empirical formulae. Tauc's plot show that the values of optical band gap energies decrease from 1.82 eV to 1.59 eV, while the assessed Urbach energies increase from 0.048 eV to 0.056 eV with Bi addition. The reflection and transmission data have been analyzed within the range of 300–800 nm. Various important optical parameters like refractive index, absorption coefficient, extinction coefficient, surface and volume energy loss functions, optical density, skin depth, third-order nonlinearity, thermal emissivity, etc., have been investigated. The Wimple Didomenico model has been used to analyze several dispersion parameters. The Chemical bond approach model has been used to estimate the cohesive energy, which is found to decrease from 2.761 eV to 2.747 eV. The increase in non-linear refractive index and third-order non-linear optical susceptibility indicates the possibility of these materials being used in optical switching devices as well as photonic devices.