Research and Technological Institute of Optical Material Science

Saint Petersburg, Russia

Research and Technological Institute of Optical Material Science

Saint Petersburg, Russia
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Anan'ev A.,Research and Technological Institute of Optical Material Science | Bogdanov V.,Saint Petersburg State University | Maksimov L.,Research and Technological Institute of Optical Material Science | Yanush O.,Saint Petersburg State University
Physics and Chemistry of Glasses: European Journal of Glass Science and Technology Part B | Year: 2012

Fluctuation inhomogeneities of inorganic glasses are considered based on light scattering spectroscopy and high temperature acoustic data. The dependencies of the Landau-Placzek ratio on glass composition were determined from Rayleigh and Mandel'shtam-Brillouin scattering (RMBS) spectra. The dependencies of the ultrasound velocities of glasses and their melts on temperature and frequency were found. Results are discussed in terms of "freezing" refractive index fluctuations during glass melt cooling. Constant stoichiomentry groupings (CSG) were found from specially processed Raman scattering spectra of glasses. In particular, highly electro-optic sensitive niobate glasses contain CSGs with stoichiometries of well-known electro-optical crystals. Selective entering, i.e. segregation, of dopants (Nb, Pb, rare earths, etc.) into inhomogeneities of a glass host causes growth of Rayleigh scattering losses and increases the probability of transfer of electron excitation energy between luminescent rare earth ions. The data obtained opens a route for developing low scattering multicomponent glasses for optical and electro-optical fibres, laser and radiation converting glasses. © 2012 Publishing Technology.


Bogdanov V.,Saint Petersburg State University | Maksimov L.,Research and Technological Institute of Optical Material Science | Anan'Ev A.,Research and Technological Institute of Optical Material Science | Nemilov S.,National Research University of Information Technologies | Rusan V.,Research and Technological Institute of Optical Material Science
IOP Conference Series: Materials Science and Engineering | Year: 2012

Rayleigh and Mandel'shtam-Brillouin scattering (RMBS) spectroscopy and high temperature ultrasonic study (HTUS) are applied to PbO-Al2O 3-B2O3 glass forming system characterized by over liquidus miscibility gap. Temperature dependences of ultrasonic velocity of glass melts were measured in 600-1200°C range. "Frozen-in" density fluctuations in two phase glasses were estimated from HTUS data by Macedo-Shroeder formulation. Landau-Placzek ratios were found from RMBS spectra of single phase glasses at room temperature. Results of RMBS and HTUS were compared with well-known SAXS data. It was found that contribution of "frozen-in" density fluctuations into light scattering by two-phase glasses is much smaller than the scattering on particles of the second glassy phase causing opalescence of the glasses. Abnormal "water-like" growth of ultrasonic velocity with melt temperature can be explained by coexistence of two types of packaging of structural elements. © Published under licence by IOP Publishing Ltd.


Maksimov L.,Research and Technological Institute of Optical Material Science | Anan'ev A.,Research and Technological Institute of Optical Material Science | Bogdanov V.,Saint Petersburg State University | Markova T.,Saint Petersburg State University | And 2 more authors.
IOP Conference Series: Materials Science and Engineering | Year: 2011

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.


Maksimov L.V.,Research and Technological Institute of Optical Material Science | Anan'Ev A.V.,Research and Technological Institute of Optical Material Science | Bogdanov V.N.,Saint Petersburg State University
IOP Conference Series: Materials Science and Engineering | Year: 2011

Glassy metaphosphates of one, two, and three valence metals were studied by Rayleigh and Mandel'shtam-Brilllouin scattering (RMBS) spectroscopy and high temperature ultrasonic (HTUS) measurements in glass melts. Ratios of Rayleigh scattering intensities to the Mandel'shtam-Brilllouin scattering ones (Landau-Placzek ratios) were measured. Results are discussed in terms of density, concentration, and anisotropy fluctuations "freezing" when the melt is being cooled to solid glass state. Combined application of RMBS and HTUS made it possible to independently estimate the contributions of "frozen-in" density and concentration fluctuations into Rayleigh scattering. It was found that in most cases about half Rayleigh scattering intensity is caused by chemical nanoinhomogeneities of a glass, that is the "frozen-in" concentration fluctuations. Comparison of RMBS, HTUS and small angle X ray scattering (SAXS) data led to the conclusion that NaPO 3 and Ba(PO3)2 glasses were characterized by the highest chemical homogeneity on nanometer scale. © Published under licence by IOP Publishing Ltd.


Gumenyuk R.,Tampere University of Technology | Gaponenko M.S.,Belarusian National Technical University | Yumashev K.V.,Belarusian National Technical University | Onushchenko A.A.,Research and Technological Institute of Optical Material Science | Okhotnikov O.G.,Tampere University of Technology
IEEE Journal of Quantum Electronics | Year: 2012

Saturable absorber based on PbS quantum-dot-doped glasses exhibiting bi-temporal recovery dynamics provides effective means for control of vector soliton bunching in 2-μ m spectral range. The slow response of absorption creates an attractive force between pulses, and a bunch of tightly bounded vector solitons propagates in a cavity as an entity. Subjected to the joint action of attractive and repulsive forces, the solitons tend to oscillate within the bunch. © 2012 IEEE.


Arbuzov V.I.,Saint Petersburg State University of Information Technologies, Mechanics and Optics | Fyodorov Yu.K.,Research and Technological Institute of Optical Material Science | Nikitina S.I.,Research and Technological Institute of Optical Material Science | Smirnov R.V.,Saint Petersburg State University of Information Technologies, Mechanics and Optics | And 2 more authors.
Physics and Chemistry of Glasses: European Journal of Glass Science and Technology Part B | Year: 2015

Russia has started construction of the 192 channel pulse amplifier facility UFL-2M with an output energy of 2·8 MJ. Large disc active elements (DAE) with a light aperture of 400×400 mm for the UFL-2M are made from a neodymium phosphate glass KNFS3 of the system Na2O-K2O-MgO-CaO-SrO-BaO-B2O3-SiO2-P2O5 with a neodymium concentration of 3·5×1020 cm-3. One of the rather effective routes that output energy decreases is the so-called parasitic generation in a DAE caused by luminescence quanta propagating along big polished planes of a DAE. The phenomenon of parasitic generation is known to lead to a significant (by tens percents) decrease in the signal gain. To suppress this phenomenon, cladding plates should be pasted to the DAE side edges that are made usually of copper-containing glasses as they have an intense absorption band with a maximum at approximately 880 nm caused by Cu2+ ions. The cladding glass, the photo-resistant glue and the DAE glass must be assembled in such a way that the refractive index, n, meets the following condition ncladngluenDAE. To eliminate thermal strains at the junction of the cladding plates and the DAE, the difference in values of coefficients of thermal expansion |α clad-αDAE | should be close to 0. The decimal coefficient of radiation absorption at the lasing wavelength 1053 nm, a1053, must be in the limits from 1·2 to 2·0 cm-1. The paper shows how such copper-containing glasses were developed that satisfy the requirements on refraction index, coefficient of thermal expansion and absorption coefficient at the lasing wavelength. Their parameters are n=1·544±0·002, n1053=1·534±0·002, α20-300=(117±2)×10-7 K-1 as compared with that of the glass KNFS3 n =1·540±0·002, n1053=1·530±0·002, α=(116±2)×10-7 K -1. The developed copper containing glasses can be used in the production of large disk active elements for the amplifier facility UFL2M.

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