Light Induced Effects in Chalcogenide Glasses, Glass-Ceramics and Crystals

Some effects induced by laser treatment in GeS2 glasses, glass-ceramics and selected chalcogenide crystals are presented. We show that thermal treatment of glasses or introducing controlled disorder in crystal lattice give the opportunity to make the desired changes in the optical and electrical properties of materials. Irradiation by CW and pulsed lasers can significantly change the absorbance and birefringence in the 400-800 nm spectral range. We have observed and measured changes of absorption and refractive index, and investigated relaxation process after switching off the irradiation. Chalcogenide crystals were promising for use in optically operated devices through their photoconductivity and efficient frequency doubling. Different possible mechanisms responsible for the effects are discussed.