Dynamic sound attenuation at hypersonic frequencies in silica glass Auteur(s): Levelut C., Le Parc R., Pelous Jacques (Article) Publié: Physical Review B, vol. 73 p.0652201 (2006) Texte intégral en Openaccess : Ref HAL: hal-00016521_v1 Ref Arxiv: cond-mat/0601096 Ref. & Cit.: NASA ADS Exporter : BibTex | endNote Résumé: In order to clarify the origin of the dominant processes responsible for the acoustic attenuation of phonons, which is a much debatted topic, we present Bril louin scattering experiments in various silica glasses of different OH impurities content. A large temperature range, from 5 to 1500 K is investigated, up to the glass transition temperature. Comparison of the hypersonic wave attenuation in various samples allows to identify two different processes. The first one induce s a low temperature peak related to relaxational processes; it is strongly sensitive to the extrinsic defects. The second, dominant in the hig h temperature range, is weakly dependent on the impurities and can be ascribed to anharmonic interactions. |