| Numéro |
J. Phys. Colloques
Volume 39, Numéro C6, Août 1978
The XVth International Conference on low temperature physicsQuantum Fluids and Solids Superconductivity |
|
|---|---|---|
| Page(s) | C6-244 - C6-245 | |
| DOI | https://doi.org/10.1051/jphyscol:19786107 | |
The XVth International Conference on low temperature physics
Quantum Fluids and Solids
Superconductivity
J. Phys. Colloques 39 (1978) C6-244-C6-245
DOI: 10.1051/jphyscol:19786107
1 Department of Physics, University of Exeter, Exeter, Devon, England.
2 Department of Physics, University of Nottingham, Nottingham, England.
3 Institute of Oceonagraphic Sciences, Taunton, England.
Quantum Fluids and Solids
Superconductivity
J. Phys. Colloques 39 (1978) C6-244-C6-245
DOI: 10.1051/jphyscol:19786107
FREQUENCY OF PHONONS EMITTED INTO LIQUID He BY A SOLID
A.F.G. Wyatt1 and G.N. Crisp2, 31 Department of Physics, University of Exeter, Exeter, Devon, England.
2 Department of Physics, University of Nottingham, Nottingham, England.
3 Institute of Oceonagraphic Sciences, Taunton, England.
Résumé
Nous avons mesuré la distribution angulaire des phonons émis par NaF avec un bolomètre qui détecte toutes les fréquences et une jonction tunnel supraconductrice qui est sensible aux phonons [MATH]ω > 2Δ. Les deux distributions sont très différentes et nous concluons que les fréquences des phonons dans le canal de fond continu sont plus faibles que dans le pic.
Abstract
We have measured the angular distribution of phonons emitted from NaF with a bolometer which detects all frequencies and a superconducting tunnel junction which is only sensitive to phonons with [MATH]ω > 2Δ. The two distributions are substantially different and we conclude that the phonon frequencies in the background channel are lower than those in the peak.