Inhomogeneous structure of inorganic glasses studied by Rayleigh, Mandel'shtam-Brillouin, Raman scattering spectroscopy, and acoustic methods

General features of inhomogeneous structure characteristic of inorganic glasses are analyzed on the base of results of combined application of light scattering spectroscopy and high temperature acoustic methods. In the framework of the model of "freezing" equilibrium thermodynamic fluctuations of melt the glass composition dependences of Landau-Placzek ratios taken from Rayleigh and Mandel'shtam-Brillouin scattering (RMBS) spectra and high temperature acoustics data for glass melts make it possible to estimate separately the relative role of "frozen-in" density and concentration fluctuations in the intensity of Rayleigh scattering (RS) by glasses. The obtained data opens the way to elaboration of glasses of the highest chemical and/or optical homogeneity for fiber and laser optics. It was found that Rayleigh scattering is sensitive to the selective entering of doped ions into concentration fluctuations of a glass host (the so-called dopant segregation phenomenon). Thus, RMBS data allows controlling the real dopant-dopant separations in glasses that are significant for the elaboration of laser glasses. Being carefully measured, the intensities of Raman scattering spectral bands can be used for the determination of concentrations and partial properties of constant stoichiometry groups (CSG) from which some binary glass forming systems are built. Comparison of RMBS and Raman scattering data leads to the conclusion that concentration fluctuations in some binary glass forming systems can be considered as fluctuations of CSGs. The result can be used for the elaboration of EO glasses with minimized RS losses.

[1]  M. Ferrari,et al.  Origin of Rayleigh scattering and anomaly of elastic properties in vitreous and molten GeO2 , 2008 .

[2]  A. A. Onushchenko,et al.  Structural Features of Nano-Scaled Metamaterials Containing PbS Nanocrystals , 2008 .

[3]  B. Champagnon,et al.  Micro- and nanoinhomogenities in glasses and their melts studied by optical, SAXS, acoustical and thermodynamic methods , 2007 .

[4]  L. Maksimov,et al.  Design of low scattering and IR transparent glasses on the base of constant stoichiometry groupings concept , 2006 .

[5]  Hypolito J. Kalinowski,et al.  Production and characterization of broad fibre Bragg gratings for photonic devices , 2005, SPIE Optics + Optoelectronics.

[6]  A. Lipovskii,et al.  Multicomponent glasses for electrooptical fibers , 2005 .

[7]  S. Mamedov,et al.  Viscoelastic properties of Na–Al–PO3 glasses and melts , 2003 .

[8]  B. Champagnon,et al.  Thermal annealing and density fluctuations in silica glass , 2001 .

[9]  Dmitry V. Svistunov,et al.  Electro-optic glasses and glass ceramics for elements controlling laser radiation , 2001, Laser Optics.

[10]  J. Bass,et al.  High-frequency relaxational spectroscopy in liquid borates and silicates , 1995 .

[11]  Harald Martens,et al.  Restricted Least Squares Estimation of the Spectra and Concentration of Two Unknown Constituents Available in Mixtures , 1982 .

[12]  A. A. Manenkov,et al.  Correlation of the efficiency of cooperative sensitization of luminescence with the intensity of Rayleigh scattering , 1977 .

[13]  J. Schroeder,et al.  Light Scattering of Glass , 1977 .

[14]  H. Dardy,et al.  Light scattering from boron trioxide through the glass transition , 1974 .

[15]  P. B. Macedo,et al.  Equilibrium Compressibilities and Density Fluctuations in K2O–SiO2 Glasses , 1973 .

[16]  I. L. Fabelinskii,et al.  Molecular scattering of light , 1968 .

[17]  H. Rawson Inorganic Glass Forming Systems , 1967 .

[18]  R. M. Wallace,et al.  A Method for the Determination of Rank in the Analysis of Absorption Spectra of Multicomponent Systems1 , 1964 .