Phonon--phonon interactions in liquid helium

Journal Article · Fri Apr 01 04:00:00 EST 1977 · Rev. Mod. Phys.; (United States)

DOI:https://doi.org/10.1103/RevModPhys.49.341· OSTI ID:7313145

Maris, H J

This is a short review of recent experimental and theoretical studies of phonon interactions in superfluid helium. Phonon--phonon scattering in helium is strongly influenced by the conservation laws and by the peculiarities of the phonon dispersion relation. Theory predicts that because of these factors the spontaneous decay rate varies dramatically with phonon energy, and experiments have confirmed this prediction. The conservation laws can also be used to show that phonon--phonon collisions are predominantly small-angle scattering. We discuss the influence of this special property of phonon collisions on the hydrodynamics of the phonon gas, and we consider the solutions of the hydrodynamic equations in several situations of experimental interest.

• Research Organization: Department of Physics, Brown University, Providence, Rhode Island 02912
• OSTI ID: 7313145
• Journal Information: Rev. Mod. Phys.; (United States), Journal Name: Rev. Mod. Phys.; (United States) Vol. 49:2; ISSN RMPHA
• Country of Publication: United States
• Language: English

Related Subjects

640450* -- Fluid Physics-- Superfluidity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ATTENUATION
DISPERSION RELATIONS
EVEN-EVEN NUCLEI
EXPANSION
FLUID MECHANICS
FREQUENCY DEPENDENCE
HELIUM 4
HELIUM II
HELIUM ISOTOPES
HYDRODYNAMICS
ISOTOPES
LIGHT NUCLEI
MECHANICS
NUCLEI
PHONONS
QUASI PARTICLES
SECOND SOUND
SOUND WAVES
STABLE ISOTOPES
SUPERFLUIDITY
THERMAL EXPANSION
ULTRASONIC WAVES
VISCOSITY
WAVE PROPAGATION