Short- and Medium-Range Order in Ge-(S, Se) Glasses Using Raman Scattering

摘要: Typical covalent chalcogenide alloy glasses, Ge-(S, Se), apply a good stage for demonstrating the constraint theory of network which predicted rigidity percolation over twenty years ago[l, 2]. Short- and medium-range order Se) glasses can be varied continuously to form both floppy rigid by changing concentration germanium. Recent important developements experimental equipment in Raman-scattering measurement enable us detect dynamics wide range temperature, even vicinity glass-transition temperature. Using Raman scattering technique, (1) we investigate ability crystallization, derives from glass forming, heating melt-quenched films room temperature up 1000K covering glassy, super cooled liquid, crystalline liquid states; (2) propose fractal-structure view explain low-frequency behaviors spectra; (3) obtain qualitative degree fragility that shows stiffness transition with connectivity changing.