Polaron-type theory for the specific heat of [sup 3]He in superfluid [sup 4]He

Journal Article · Fri Oct 01 04:00:00 EDT 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.48.9669· OSTI ID:5945361

Lemmens, L F; Witters, J; Brosens, F; Devreese, J T ^[1]

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1. Departement Natuurkunde, Universiteit Antwerpen (Rijksuniversitaire Centrum Antwerpen and Universitaire Instelling Antwerpen), Groenenborgerlaan 171, B-2020 Antwerpen (Belgium)

The difference between the specific heat of a dilute [sup 3]He-[sup 4]He mixture and the specific heat of pure superfluid [sup 4]He at temperatures below the superfluid transition temperature is usually explained by considering the [sup 3]He as an ideal gas of quasiparticles with an energy spectrum that is not quadratic in the momentum, but which is difficult to justify on a theoretical basis. On the basis of a polaron-type model, introduced by three of the present authors, the specific heat of the mixture can be calculated, taking into account the emission and absorption of the phonon-roton excitations. In a temperature range where the [sup 3]He particles follow Boltzmann statistics, we find that the model accurately explains the experimental data for the specific heat. Therefore, the difference between the specific heat of the mixture and the specific heat of pure superfluid [sup 4]He can be explained as the result of the interaction of [sup 3]He with the excitations of the superfluid. Moreover, it is one of the most clearly measured polaron'' effects.

• OSTI ID: 5945361
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 48:13; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

665420* -- Superfluidity-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FERMI GAS
FLUIDS
GASES
HELIUM 3
HELIUM 4
HELIUM ISOTOPES
ISOTOPES
LIGHT NUCLEI
NUCLEI
PHONONS
PHYSICAL PROPERTIES
POLARONS
QUASI PARTICLES
ROTONS
SPECIFIC HEAT
STABLE ISOTOPES
SUPERFLUIDITY
TEMPERATURE DEPENDENCE
THERMODYNAMIC PROPERTIES