In-situ real-time simultaneous measurements of photoinduced bandgap and volume changes in amorphous chalcogenide films

To understand the dynamics and correlations between photodarkening (PD) and photoinduced volume changes (PVC) in amorphous chalcogenides, a simultaneous PD and PVC measuring system based on computer analyzed spectroscope and phase-shifting interferometer (PSI) has been developed. This new system provides us the records of both PD and PVC in amorphous chalcogenides during illumination with common time axis. The time evolutions of PD and PVC are represented by a stretched exponential function and a just exponential function, respectively, suggesting that the dynamics of the PD is different from the PVC in a-As2Se3 films.