Effect of UV Exposure on Some Optical Properties of As-Se Based Chalcogenide Glasses

Bulk As40Se60 glass was prepared by melt quenching technique. Amorphous films of As40Se60 were prepared by thermal evaporation technique then exposed in UV light for 10 minutes. Virgin and exposed thin films were analyzed using transmission spectra to determine thickness (d), refractive index (n), extinction coefficient (k), optical absorption coefficient (alpha), optical band gap (E-g) and real and imaginary parts of dielectric constants (epsilon ' and epsilon ''). Results show 10 minutes UV exposure cause photodarkening (red shift in the optical band gap) and photorefraction (increase in refractive index) in As40Se60 thin film, which can be utilized for various photonic applications.