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Sound attenuation in an unexplored frequency region: Brillouin Ultraviolet Light Scattering measurements in v-SiO2

P. Benassi·S. Caponi·R. Eramo·A. Fontana·A. Giugni·M. Nardone·M. Sampoli·G. Viliani
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Abstract

We report Ultraviolet Brillouin light scattering experimental data on v-SiO2 in an unexplored frequency region, performed with a newly available spectrometer up to exchanged wavevector q values of 0.075 nm^{-1}, as a function of temperature. The measured attenuation scales on visible data following a q^2 behavior and is temperature-dependent. Such temperature dependence is found in a good agreement with that measured at lower q, suggesting that its origin is mainly due to a dynamic attenuation mechanism. The comparison between the present data with those obtained by Inelastic X-ray Scattering suggests the existence of a cross-over to a different attenuation regimes.

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P. Benassi, S. Caponi, R. Eramo, A. Fontana, A. Giugni, M. Nardone, M. Sampoli, G. Viliani. 2004-07-19. Sound attenuation in an unexplored frequency region: Brillouin Ultraviolet Light Scattering measurements in v-SiO2. https://arxiv.org/abs/cond-mat/0407476

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