J. Phys. Colloques
Volume 42, Numéro C6, Décembre 1981International Conference on Phonon Physics
|Page(s)||C6-72 - C6-74|
J. Phys. Colloques 42 (1981) C6-72-C6-74
ATTENUATION AND VELOCITY CHANGE OF ACOUSTIC WAVES IN THE AMORPHOUS METAL PdSiCu FROM 0.05 K TO 90 KP. Doussineau
Laboratoire d'Ultrasons, Université Pierre et Marie Curie, Tour 13, 4 place Jussieu, 75230 Paris Cedex 05, France
Previous acoustic experiments in a-PdSiCu were extended. Attenuation and velocity change were measured at various frequencies around 500 MHz from 0.05 K to 90 K . The attenuation is interpreted as the sum of two contributions : one due to the relaxation of the TLS and the other due to an activated process. The velocity change is explained with the same two preceding contributions ; however it is necessary to add not only the resonant contribution but also an electronic term varying as T2.