Related papers: Raman scattering as a probe of intermediate phases…
The nature of enhanced photoemission in disordered and amorphous solids is an intriguing open question. A point in case is light emission in silicon, which occurs when the material is porous or nanostructured, but the effect is absent in…
We report on an inelastic (Raman) light scattering study of the local structure of amorphous GeTe films. A detailed analysis of the temperature-reduced Raman spectra has shown that appreciable structural changes occur as a function of…
Raman scattering, IR reflectance and modulated DSC measurements are performed on specifically prepared dry (AgI)x(AgPO3)1-x glasses over a wide range of compositions 0 < x < 0.60. A reversibility window is observed in the 0.095< x < 0.378…
The structure of binary As_xS_{1-x} glasses is elucidated using modulated-DSC, Raman scattering, IR reflectance and molar volume experiments over a wide range (8%<x<41%) of compositions. We observe a reversibility window in the calorimetric…
The rigid to floppy transitions and the associated intermediate phase in glasses are studied in the case where the local structure is not fully determined from the macroscopic concentration. The approach uses size increasing cluster…
We review in this paper the signatures of a new elastic phase that is found in glasses with selected compositions. It is shown that in contrast with random networks, where rigidity percolates at a single threshold, networks that are able to…
A novel form of amorphous matter characterized by marginal stability was recently discovered in the mean-field theory of structural glasses. Using this approach, we provide complete phase diagrams delimiting the location of the marginally…
Much progress has been made over a long period, spanning more than a century, in understanding the atomic arrangement on various length scales of noncrystalline chalcogens and their transitions upon certain external stimuli. However, it is…
Liquid water and vitreous B$_2$O$_3$ are the endpoints of a continuous range of random networks in which hydrogen bonds gradually replace covalent bonds. Previous work has shown that glasses can be obtained by quenching in the range $x \le$…
The effects of plasticization of poly(methyl methacrylate) glass on the boson peaks observed by Raman and neutron scattering are compared. In plasticized glass the cohesion heterogeneities are responsible for the neutron boson peak and…
The Raman effect -- inelastic scattering of light by lattice vibrations (phonons) -- produces an optical response closely tied to a material's crystal structure. Here we show that resonant optical excitation of IR and Raman phonons gives…
Transparent glass ceramic materials, with microstructures comprised of dispersed nanocrystallites in a residual glass matrix, offer the prospect of nonlinear optical properties. However, good transparency requires low optical scattering and…
A Raman profiling method is used to monitor growth of GexSe100-x melts and reveals a two step process of homogenization. Resulting homogeneous glasses show the non-reversing enthalpy at Tg, {\Delta}Hnr(x), to show a square-well like…
There is growing evidence that electronic and molecular networks present some common universal properties, among which the existence of a self-organized intermediate phase. In glasses, the latter is revealed by the reversibility window…
Glass phases can be stabilized by quenched disorders, as in most spin-glass materials, or self-generated through kinetic freezing in disorder-free systems. A canonical example of the latter is structural glasses, which have been extensively…
Alkaline earth silicate glasses $xCaO-(1-x)SiO_2$ exhibit a well marked threshold in Raman lineshapes which can be related to the onset of network rigidity as the concentration of calcium oxide $x$ is decreased. The present results are…
Propagation of light in a highly scattering medium is among the most fascinating optical effect that everyone experiences on an everyday basis and possesses a number of fundamental problems which have yet to be solved. Conventional wisdom…
Near-bandgap Raman scattering was used to induce and study photostructural changes in AsxS100-x bulk glasses revealing a new photoinduced polymerization effect. Raman spectra were recorded also in off-resonant conditions allowing for a…
Systematic Raman experiments performed on water and water-ethanol samples, stored in different containers (fused silica, polypropylene, soda-lime glass type III) for several hours, have shown that the luminescence contribution to the Raman…
Experimental results for covalent glasses have highlighted the existence of a new self-organized phase due to the tendency of glass networks to minimize internal stress. Recently, we have shown that an equilibrated self-organized…