Observation of the onset of strong scattering on high frequency acoustic phonons in densified silica glass.

نویسندگان

  • B Rufflé
  • M Foret
  • E Courtens
  • R Vacher
  • G Monaco
چکیده

The linewidth of longitudinal acoustic waves in densified silica glass is obtained by inelastic x-ray scattering. It increases with a high power alpha of the frequency up to a crossover where the waves experience strong scattering. We find that alpha is at least 4, and probably larger. Resonance and hybridization of acoustic waves with the boson-peak modes seems to be a more likely explanation for these findings than Rayleigh scattering from disorder.

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عنوان ژورنال:
  • Physical review letters

دوره 90 9  شماره 

صفحات  -

تاریخ انتشار 2003