Photoinduced nonlinear optics in Sb2Se3-BaCl2-PbCl2 glasses

Photoinduced structural transformations in amorphous Sb2Se3-BaCl2-PbCl2 gla sses were studied using a differential IR spectroscopy Fourier technique in the spectral region between 100 and 300 cm(-1). A stage of the reversible photodarkening is realized in the Sb2Se3 fragments after the first cycle of photoexposure and thermoannealing. The whole scheme of the photo- and ther moinduced transformations in the amorphous system may be explained as a coo rdination of formation and annihilation of defects. The vibrational density of states calculated using quantum chemical solid state methods confirms o ur experimental results and their interpretation. Photoinduced photodarkeni ng changes using a CO2 pulse laser (lambda = 10.6 mu m) in new synthesized Sb2Se3-BaCl2-PbCl2 glasses were investigated. At the same time we have stud ied photoinduced second harmonic generation (SHG) and two-photon absorption (TPA). The possibility of using this glass as perspective materials for IR optoelectronics and nonlinear optics was shown. (C) 1999 Elsevier science B.V. All rights reserved.