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q-dependence of low-frequency Raman scattering in silica glass

N. V. Surovtsev·J. Wiedersich·V. N. Novikov·E. R"ossler·E. Duval
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Abstract

Accurate measurements of the dependence of low-frequency Raman scattering on the scattering angle were performed in two silica glasses. By a comparison of spectra measured at a large scattering angle (close to back scattering) and a small one (close to forward scattering), we for the first time observed a q-dependence of the low-frequency light scattering in glasses. From the magnitude of the effect, the vibration correlation length is estimated and compared with results from the picosecond optical technique; a reasonable agreement is found.

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N. V. Surovtsev, J. Wiedersich, V. N. Novikov, E. R"ossler, E. Duval. 1999-04-27. q-dependence of low-frequency Raman scattering in silica glass. https://doi.org/10.1103/physrevlett.82.4476

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