Investigation of the phonon dispersion relation in liquidby thermal-expansion measurements
- 1 September 1976
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review B
- Vol. 14 (5), 1902-1910
- https://doi.org/10.1103/physrevb.14.1902
Abstract
The thermal expansion of superfluid under the saturated vapor pressure has been measured in the temperature range 0.1-0.62 K. The expansion was found by filling a superconducting resonant cavity with the liquid and measuring the resonant frequency as a function of temperature. The density was related to the dielectric constant through the Clausius-Mossotti relation. Sensitivity to changes in fractional density of 4 × was achieved. The thermal-expansion data were used to obtain quantitative information about the dispersion relation for thermal phonons. In addition to the thermal-expansion measurements, tests of the validity of the Clausius-Mossotti relation were made.
This publication has 37 references indexed in Scilit:
- Frequency and Temperature Dependence of Sound Velocity in Liquid Helium-4: A Test of the Phonon Dispersion RelationPhysical Review Letters, 1975
- Evidence for Upward or "Anomalous" Dispersion in the Excitation Spectrum of He IIPhysical Review Letters, 1974
- Evidence for Upward Phonon Dispersion in Liquidfrom the Angular Spreading of Phonon BeamsPhysical Review Letters, 1974
- Hydrodynamics of Superfluid Helium below 0.6°K. II. Velocity and Attenuation of Ultrasonic WavesPhysical Review A, 1973
- Hydrodynamics of Superfluid Helium below 0.6 °K.I. Viscosity of the Normal FluidPhysical Review A, 1973
- Temperature dependence of the sound velocity in liquid4HeJournal of Low Temperature Physics, 1972
- Positive Linear Dispersion in the Velocity of Sound in He IIPhysical Review Letters, 1972
- Calorimetric Evidence for Positive Phonon Dispersion in Liquid Helium-4Physical Review Letters, 1970
- Sound Propagation in LiquidPhysical Review B, 1969
- Experiments on the flow of heat in liquid helium below 0.7 °KProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1958