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Non-dynamic origin of the acoustic attenuation at high frequency in glasses

G. Ruocco·F. Sette·R. Di Leonardo·D. Fioretto·M. Lorenzen·M. Krisch·C. Masciovecchio·G. Monaco·F. Pignon·T. Scopigno
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Abstract

The sound attenuation in the THz region is studied down to T=16 K in glassy glycerol by inelastic x-ray scattering. At striking variance with the decrease found below 100 K in the GHz data, the attenuation in the THz range does not show any T dependence. This result i) indicates the presence of two different attenuation mechanisms, active respectively in the high and low frequency limits; ii) demonstrates the non-dynamic origin of the attenuation of THz sound waves, and confirms a similar conclusion obtained in SiO2 glass by molecular dynamics; and iii) supports the low frequency attenuation mechanism proposed by Fabian and Allen (Phys.Rev.Lett. 82, 1478 (1999)).

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G. Ruocco, F. Sette, R. Di Leonardo, D. Fioretto, M. Lorenzen, M. Krisch, C. Masciovecchio, G. Monaco, F. Pignon, T. Scopigno. 1999-11-02. Non-dynamic origin of the acoustic attenuation at high frequency in glasses. https://arxiv.org/abs/cond-mat/9911012

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