The recently developed technique of Brillouin ultraviolet scattering is used to measure phonon dispersion and damping in the prototypical strong glass v-SiO2. Results on the low temperature (T similar to 10-100 K) sound attenuation at a frequency of similar to 66GHz are presented. The comparison between a model, which takes into account dynamical processes (thermally activated relaxations and the interaction with the bath of thermal vibrations), and the experimental data indicates the presence of a strong static contribution in the region explored by Ultraviolet radiation, supporting the presence of a transition between static and dynamic attenuation mechanisms at a frequency of similar to 100GHz.
Low-temperature phonon damping in vitreous silica explored by UV Brillouin spectroscopy
Baldi G;Caponi S;
2007
Abstract
The recently developed technique of Brillouin ultraviolet scattering is used to measure phonon dispersion and damping in the prototypical strong glass v-SiO2. Results on the low temperature (T similar to 10-100 K) sound attenuation at a frequency of similar to 66GHz are presented. The comparison between a model, which takes into account dynamical processes (thermally activated relaxations and the interaction with the bath of thermal vibrations), and the experimental data indicates the presence of a strong static contribution in the region explored by Ultraviolet radiation, supporting the presence of a transition between static and dynamic attenuation mechanisms at a frequency of similar to 100GHz.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
