Laser-induced diffraction patterns in germanium diselenide amorphous films.
We report the characterization of changes produced on germanium diselenide amorphous semiconductor thin films by a focused He-Ne laser beam. The diffraction pattern produced by the laser spot on the sample is studied as a function of the intensity and the irradiation time. At low intensities the state of polarization of the incident beam generates an asymmetry in the induced diffraction pattern. Moreover, if the polarization of the incident beam is rotated, the corresponding asymmetry rotates as well. These results show the difference between thermal and electromagnetic effects on the material. This system may be used as a high density recording medium.
Photodarkening and light induced anisotropy in chalcogenide glasses
Abstract A unified description of photodarkening and light induced anisotropy in chalcogenide glasses is presented in terms of bistable atomic configurations
Time behavior of gas pressure and PD activity in insulation cavities under AC voltage
In the framework of developing defect-based life models (i.e. the life model of partial discharge-induced damage growth from a micro-void in polymer matrix), ageing tests were performed on PE layered specimens with artificial cavities under constant gas pressure and constant gas volume conditions, respectively. Time behavior of the discharge repetition rate and amplitude were recorded and compared under these two conditions. Results show that pressure variation has little influence on PD activities at constant gas volume. Under constant gas pressure, the evolution of gas volume has similar characteristic to the product of discharge amplitude and repetition rate.