Analysis of photodarkening kinetics in the pulsed laser deposited As/sub 2/S/sub 3/ films

Summary form only given. Chalcogenide glasses are low phonon energy materials and hence are transparent from the visible up to the infrared. These glasses are susceptible to electromagnetic radiation and show a wide variety of photoinduced effects as a result of illumination. These photoinduced effects can be used to fabricate diffractive as well as waveguide structures in these glasses. Up to now thermally evaporated and sputtered films have been mainly used for fabrication of these structures in chalcogenide glasses. We deposited up to 5 pm thick As/sub 2/S/sub 3/-glass films using high-repetition-rate laser ablation with the second harmonic of a Nd:YAG laser. The possibility of producing films by the laser ablation facilitates fabrication of devices with low scattering centres. Until now very little work has been done to fabricate structures in the pulsed laser deposited films and these works have been limited to films of Ga-La-S glasses. As a result of illumination photodarkening has been observed in the laser-deposited As/sub 2/S/sub 3/ films for the first time.