Texture and hydrodynamics of a thin slab of superfluid /sup 3/He-A in a torsional oscillator. II. Experiment

Journal Article · Sat Dec 31 23:00:00 EST 1988 · J. Low Temp. Phys.; (United States)

DOI:https://doi.org/10.1007/BF00681752· OSTI ID:5811722

Hook, J R; Faraj, E; Gould, S G; Hall, H E

Experiments on a torsional oscillator containing a slab of liquid /sup 3/He of thickness 105 /mu/m and diameter 8.38 mm are described. Normal phase experiments confirm the theory of the oscillator dynamics but an apparent decrease in the measured value of /eta/T/sup 2/ at low T casts doubt on the existing slip theory. Measurements for the uniform texture for the A phase give values of /rho//sub s/perpendicular// and /eta//sup 44/. The /rho//sub s/perpendicular// measurements suggest that the A-phase energy gap is enhanced by a factor 1.24 over the BCS value. Distortion of the uniform texture by a magnetic field perpendicular to the slab occurs at a threshold field slightly smaller than predicted. Measurements for fields at different angles to the slab enable accurate values to be deduced for the superfluid density anisotropy and two other viscosity coefficients. The remaining two viscosity coefficients are only poorly determined. Flow alignment of the orbital texture was achieved by increasing the oscillator amplitude. A different texture obtained on some occasions after warming from the B phase was investigated but is not understood.

• Research Organization: Manchester Univ. (England)
• OSTI ID: 5811722
• Journal Information: J. Low Temp. Phys.; (United States), Journal Name: J. Low Temp. Phys.; (United States) Vol. 74:1-2; ISSN JLTPA
• Country of Publication: United States
• Language: English

Related Subjects

640430 -- Fluid Physics-- Magnetohydrodynamics
640450* -- Fluid Physics-- Superfluidity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMPLITUDES
ANISOTROPY
CALIBRATION
DENSITY
ELECTRONIC EQUIPMENT
ENERGY GAP
EQUIPMENT
EVEN-ODD NUCLEI
FLUID FLOW
FLUID MECHANICS
FREQUENCY MEASUREMENT
HELIUM 3
HELIUM 3 A
HELIUM ISOTOPES
HYDRODYNAMICS
ISOTOPES
LIGHT NUCLEI
MAGNETIC FIELDS
MAGNETIC PROPERTIES
MAGNETIC SUSCEPTIBILITY
MAGNETOHYDRODYNAMICS
MECHANICS
NUCLEI
OSCILLATIONS
OSCILLATORS
PHASE STUDIES
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
SLABS
STABLE ISOTOPES
SUPERFLUIDITY
TEMPERATURE DEPENDENCE
TEMPERATURE MEASUREMENT
TEST FACILITIES
TEXTURE
TORSION
VISCOSITY
VISCOUS FLOW