Photo induced anisotropy in the AgGaGe3Se8:Cu chalcogenide crystals

The occurrence of huge optical anisotropy detected by birefringence measurements in single crystals of AgGaGe3Se8:Cu was discovered under influence of the continuous wave (cw) laser at wavelengths 532nm and 1300nm with averaged power equal to about 150mW. The changes of the birefringence demonstrate substantial changes of time kinetics depending on the pumping wavelengths. It was found that the changes of the photoinduced birefringence are at least 4 times higher for the 532nm pumping wavelength with respect to the 1300nm wavelength. The Ag cations, Cu dopants and local trapping levels play here crucial role. •laser induced anistropy was discovered in the AgGaGe3Se8:Cu crystals.•The addition of the Cu2+ ions substantially changes the photoinduced changes.•The time kinetics is the same during the relaxation corresponding to switching off of the laser.