Photo-induced crystallization in amorphous GeSe2 studied by Raman scattering

The structural difference, due to different preparation methods, in glassy GeSe2 samples is investigated by photo-induced crystallization phenomena using time-resolved Raman measurement. Crystallization temperatures of two samples, which were cooled from melts at different cooling rates, were almost the same in thermal crystallization processes. However, in photo-induced crystallization processes, threshold temperatures of the crystallization directly depended on their cooling rates, the smaller cooling rate the lower the threshold temperature. In the sample cooled at a smaller cooling rate, its medium-range structure is more similar to crystalline nuclei, or easier to transform into crystalline nuclei. (C) 1998 Elsevier Science B.V. All rights reserved.