Anharmonic vs. relaxational sound damping in glasses: I. Brillouin scattering from densified silica

Abstract

This series discusses the origin of sound damping and dispersion in glasses. In particular, we address the relative importance of anharmonicity versus thermally activated relaxation. In this first article, Brillouin-scattering measurements of permanently densified silica glass are presented. It is found that in this case the results are compatible with a model in which damping and dispersion are only produced by the anharmonic coupling of the sound waves with thermally excited modes. The thermal relaxation time and the unrelaxed velocity are estimated.

9 pages with 7 figures, added references

References in corpus (7)

• Anharmonicity, vibrational instability and Boson peak in glasses
• Thermal Expansion and Gruneisen Parameters of Amorphous Silicon: A Realistic Model Calculation
• Observation of the onset of strong scattering on high frequency acoustic phonons in densified silica glass
• Theory of sound attenuation in glasses: The role of thermal vibrations
• Spectral Shape of Relaxations in Silica Glass
• Interaction of quasilocal harmonic modes and boson peak in glasses
• The crossover from propagating to strongly scattered acoustic modes of glasses observed in densified silica

Cited by in corpus (7)

• Glass-specific behavior in the damping of acoustic-like vibrations
• Scaling the Temperature-dependent Boson Peak of Vitreous Silica with the high-frequency Bulk Modulus derived from Brillouin Scattering Data
• Vitreous silica distends in helium gas: acoustic vs. static compressibilities
• Correlation between vibrational anomalies and emergent anharmonicity of local potential energy landscape in metallic glasses
• Dynamic sound attenuation at hypersonic frequencies in silica glass
• Akhiezer Mechanism Dominates Relaxation of Propagons in Amorphous at Room Temperature
• Acoustic damping in Li${}_2$O-2B${}_2$O${}_3$ glass observed by inelastic x-ray and optical Brillouin scattering