Zero sound and atomiclike excitations: The nature of phonons and rotons in liquid sup 4 He

Journal Article · Mon Sep 17 04:00:00 EDT 1990 · Physical Review Letters; (USA)

DOI:https://doi.org/10.1103/PhysRevLett.65.1454· OSTI ID:6314271

Glyde, H R ^[1]; Griffin, A ^[2]

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1. Department of Physics, University of Alberta, Edmonton, Alberta (Canada)
2. Department of Physics, University of Toronto, Toronto, Ontario (Canada)

We present a novel interpretation of the traditional Landau-Feynman picture of excitations in superfluid {sup 4}He. Detailed consideration of neutron-scattering data on the temperature dependence of {ital S}({bold Q},{omega}) in the region 0.4{approx lt}{ital Q}{approx lt}2 A{sup {minus}1} strongly suggests that while the photon is a collective zero-sound mode, the maxon roton is a strongly renormalized single-particle excitation. The condensate-induced hybridization of these two modes explains the smooth photon-maxon-roton dispersion curve as well as the vanishing intensity of the maxon-roton peak in {ital S}({bold Q},{omega}) above {ital T}{sub {lambda}}.

• DOE Contract Number: FG02-84ER45082
• OSTI ID: 6314271
• Journal Information: Physical Review Letters; (USA), Journal Name: Physical Review Letters; (USA) Vol. 65:12; 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
COHERENT SCATTERING
COLLECTIVE EXCITATIONS
DATA
DIFFRACTION
ENERGY-LEVEL TRANSITIONS
EVEN-EVEN NUCLEI
EXCITATION
FREQUENCY DEPENDENCE
HELIUM 4
HELIUM ISOTOPES
HYBRIDIZATION
INFORMATION
ISOTOPES
LAMBDA POINT
LANDAU LIQUID HELIUM THEORY
LIGHT NUCLEI
NEUTRON DIFFRACTION
NUCLEI
NUMERICAL DATA
PHONONS
PHYSICAL PROPERTIES
QUASI PARTICLES
RESOLUTION
ROTONS
SATURATION
SCATTERING
STABLE ISOTOPES
STRUCTURE FACTORS
TEMPERATURE DEPENDENCE
THEORETICAL DATA
THERMODYNAMIC PROPERTIES
THREE-DIMENSIONAL CALCULATIONS
TRANSITION TEMPERATURE
ULTRALOW TEMPERATURE
VAPOR PRESSURE
VERY LOW TEMPERATURE
ZERO SOUND