In situ simultaneous measurements of photodarkening and photoinduced volume changes in chalcogenide glasses

To understand the dynamics and correlations between photodarkening (PD) and photoinduced volume changes (PVC) in chalcogenide glasses, we built up an in situ simultaneous PD and PVC measuring system based on a computer controlled spectroscope and a phase-shifting interferometer (PSI). This new system provides us the records of both PD and PVC in chalcogenide glasses during illumination with a common time axis. We have observed that the PVC reaches equilibrium faster than the PD in a-As2Se3 films.