Roton-roton scattering in liquid sup 4 He: A direct observation

Journal Article · Mon Mar 19 04:00:00 EST 1990 · Physical Review Letters; (USA)

DOI:https://doi.org/10.1103/PhysRevLett.64.1393· OSTI ID:7002713

Forbes, A C; Wyatt, A F.G. ^[1]

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1. Department of Physics, University of Exeter, Exeter EX14QL, United Kingdom (GB)

We have directly observed the effects of roton-roton scattering by crossing two beams of ballistic rotons in liquid {sup 4}He at a temperature of {approx}0.1 K. One beam is weak and is used as the probe. Its attenuation is measured as it passes through the stronger scattering beam which is predominantly perpendicular to the probe beam. The beams are pulsed and the dispersion of the roton velocities enable the momenta of the rotons to be resolved by time-of-flight measurements. It appears that the scattering is strongly wave-vector dependent.

• OSTI ID: 7002713
• Journal Information: Physical Review Letters; (USA), Journal Name: Physical Review Letters; (USA) Vol. 64:12; ISSN PRLTA; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

640450* -- Fluid Physics-- Superfluidity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ATTENUATION
DATA
DISPERSION RELATIONS
EVEN-EVEN NUCLEI
EXPERIMENTAL DATA
HELIUM 4
HELIUM ISOTOPES
INFORMATION
ISOTOPES
LIGHT NUCLEI
NUCLEI
NUMERICAL DATA
PULSES
QUASI PARTICLES
RESOLUTION
ROTONS
SCATTERING
STABLE ISOTOPES
TIME-OF-FLIGHT METHOD
ULTRALOW TEMPERATURE