Vortex dynamics and persistent current decay in thin superfluid /sup 4/He films

Journal Article · Fri Jan 01 04:00:00 EST 1982 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.25.198· OSTI ID:5848205

Yu, L

A systematic analysis of vortex dynamics based on the Kosterlitz-Thouless theory for two-dimensional phase transitions is carried out to study theoretically the decay of persistent current in thin superfluid helium films. The relaxation of vortex density due to both bulk and edge processes is considered in parallel with the dissipation of persistent current. The relaxation effects are shown to be important for thin films where bulk processes dominate, but not for thick films with prevailing wall processes. The pinning-center effects are studied within a phenomenological model and turn out to play an essential role for films of intermediate thickness at the late stage of current decay. The screening due to free vortices is discussed self-consistently in the Debye-Hueckel approximation and is shown to be substantial in the onset region. The theoretical results are compared quantitatively with the experimental data of Ekholm and Hallock (Phys. Rev. B 21, 3902 (1980)) on persistent current decay. The memory effect observed in experiment is interpreted as a consequence of the vortex density relaxation.

• Research Organization: Lyman Laboratory of Physics, Harvard University, Cambridge, Massachusetts 02138
• OSTI ID: 5848205
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 25:1; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

640450* -- Fluid Physics-- Superfluidity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
EVEN-EVEN NUCLEI
FILMS
FLUIDS
HELIUM 4
HELIUM II
HELIUM ISOTOPES
ISOTOPES
LIGHT NUCLEI
NUCLEI
ORDER-DISORDER TRANSFORMATIONS
PHASE TRANSFORMATIONS
QUANTUM FLUIDS
RELAXATION
STABLE ISOTOPES
SUPERFLUIDITY
TWO-DIMENSIONAL CALCULATIONS
VORTICES