Effect of compositional dependence on physical and optical parameters of Te17Se83−xBix glassy system

• Physical and optical parameters have been analyzed for Te17Se83−xBix glassy alloys.
• The addition of Bi leads to decrease of average heat of atomization and cohesive energy.
• The optical band gap decreases with increasing Bi content.
• The third order susceptibility and nonlinear refractive index show an increase with increase in the Bi content.

In the present paper we have studied the effect of Bi addition on the physical and optical properties of thermally evaporated Te17Se83−xBix thin films. With Bi addition the density, mean coordination number, mechanical constraints, glass transition temperature increases. The other parameters theoretical energy gap, lone pair electron, deviation from stoichiometry decreases. Transmission spectra have been taken in the spectral range 400 nm–2500 nm using ultraviolet–visible–near infrared spectrophotometer. The fundamental absorption edge shifts towards longer wavelength with Bi incorporation. Optical energy gap and linear refractive index have been determined using transmission spectra. A good correlation has been drawn between the optical and theoretical parameters. Using linear optical parameters, the nonlinear optical susceptibility and nonlinear refractive index have been estimated.