Department of Physics, Panjab University, Chandigarh, India

Department seminar

Date and time: 4 March 2014 (Tuesday), 3:00 pm
Venue: HPCC Room

Title: Modification of optical parameters of selenium based semiconducting films

Speaker: Dr. S.K. Tripathi, Department of Physics, Panjab University, Chandigarh

Abstract: Photosensitivity of chalcogenide glasses, which arises from structural rearrangements induced by the absorption of light at frequencies near the absorption band edge of the material, has been successfully utilized for the creation of directly written waveguides, strong Bragg gratings and for post tuning of optical components such as distributed feedback lasers and quantum cascade lasers. These structural rearrangements lead to changes in the properties of the glass such as the refractive index, extinction coefficient, energy gap and density. The optical parameters of these glasses can be modified using different sources like laser, proton, SHI annealing etc. The magnitude and sign of these energy induced changes can be highly dependant on the chemical composition of the glass and on the processing history of the sample. The present talk will summarizes the progress made in this direction to tune the optical parameters of Se based Chalcogenide glasses from application point of view. The third order optical susceptibility has been calculated at different wavelengths in these thin films. Some of the recent work which is going on in the laboratory will also be presented during the talk.