Photoinduced fluidity in chalcogenide glasses

Abstract

Chalcogenide glasses such as As 2 S 3 show prominent fluidity under intense subgap illumination. The feature is summarized, and the mechanism is discussed. To cite this article: K. Tanaka, C. R. Chimie 5 (2002) 805-811 © 2002 Académie des sciences / Éditions scientifiques et médicales Elsevier SAS chalcogenide glass / fluidity / viscosity / photoinduced phenomena / band gap / As 2 S 3 Résumé -Cet article décrit le phénomène exceptionnel de fluidité présenté par des verres de chalcogénures quand ils sont illuminés par des photons d'énergie inférieure à celle de la bande interdite. Pour citer cet article : K. Tanaka, C. R. Chimie 5 (2002) 805-811 © 2002 Académie des sciences / Éditions scientifiques et médicales Elsevier SAS verres de chalcogénures / fluidité / viscosité / phénomènes photo-induits / band gap / As 2 S 3

Mechanical model of giant photoexpansion in a chalcogenide glass and the role of photofluidity

“…We also assume that photoexpansion occurs in a viscoelastic medium. Indeed, under irradiation, chalcogenide glasses undergo a large and athermal viscosity decrease named photofluidity or photoinduced fluidity [11]. The viscosity under irradiation is inversely proportional to the number of photons absorbed per second per atom [30,31] and does not depend on the stress [32]: this further justifies the assumption that irradiated glasses undergo a linear viscoelastic behavior.…”

“…Chalcogenide glasses are also photosensitive materials. They exhibit a wide range of photoinduced phenomena [7,8] including: photodarkening/bleaching [9], photoinduced fluidity [10,11], photoinduced structural relaxation [12,13], photoinduced expansion [14] or contraction 2 [15], etc. Some of these effects can be scalar or vectorial, i.e.…”

“…Some photoinduced effects are much more pronounced in the sub-bandgap range [17], including giant photoexpansion-contraction [14,15], photofluidity [10,11] and photoinduced structural relaxation [18], because, sub-bandgap light permits to illuminate a larger volume. In addition, above bandgap irradiation is associated with high absorption that is sufficient to induce a significant warming and even potential damage, while sub-bandgap irradiation has a negligible thermal contribution under standard irradiation power.…”

Photo-induced phenomena in chalcogenide glass: Comparison with those in oxide glass and polymer

“…Marked volume changes [9,10,15], anisotropic deformations [10,15,19], fluidity [20,21], and mechanical motions [22,23] can be induced commonly.…”

Composition and local atomic environment in As₂Se₃ films and their changes under the coherent radiation

“…Вони є перспективними матеріалами для застосування в нано та оптоелектроніці завдяки структурним, електронним та оптичним властивостям у широкому спектральному діапазоні [1] і широко використовуються в якості матеріалів для інфрачервоної (ІЧ) оптики завдяки високій оптичній прозорості. Крім того, у халькогенідних стеклах під дією лазерного випромінювання відбуваються зміни як властивостей, так і структури [2,3].…”