Unusual hydrodynamics of the A-phase of helium three

Thesis/Dissertation · Mon Jan 01 04:00:00 EST 1979

OSTI ID:6265324

Williams, M R

The structure of bulk textures in the superfluid A phase of helium three in the presence of steady flow and parallel applied magnetic field is investigated using a simple hydrodynamical model. The uniform texture is studied and found to be stable for only a limited range of temperature, magnetic field, and superflow. The instability of the hydrodynamically stressed uniform state signals the formation of stable helical textures. These helical textures are carefully investigated, focusing especially on the textures that develop from the uniform state upon application of a magnetic field to a system supporting superflow. Two methods of establishing a superflow are considered: externally supplied heat flow within the sample and persistent current in a toroidal container. In both systems, helices are shown to be stable for a wide range of temperature, magnetic field, and superflow, but there are important regions where the helical textures are unstable. Near T/sub c/, helices that develop from the uniform state upon application of a magnetic field become unstable under increased magnetic stress when the opening angle of the helix is approximately 35/sup 0/. Using a nonlinear analysis, the instability of these helical textures is shown to arise from a catastrophic inverted bifurcation that may signal that onset of time-dependent dissipative textures rather than a small second-order distortion of the helical states. The possible character of these time-dependent states is considered. The behavior of these textures in a heat flow and in a persistent current is shown to be strikingly different.

• Research Organization: Stanford Univ., CA (USA)
• OSTI ID: 6265324
• Country of Publication: United States
• Language: English

Related Subjects

640450* -- Fluid Physics-- Superfluidity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
EVEN-ODD NUCLEI
FLUID FLOW
HELICAL INSTABILITY
HELIUM 3
HELIUM 3 A
HELIUM ISOTOPES
INSTABILITY
ISOTOPES
LIGHT NUCLEI
MAGNETIC FIELDS
NONLINEAR PROBLEMS
NUCLEI
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
STABLE ISOTOPES
TEMPERATURE DEPENDENCE
TEXTURE
ULTRALOW TEMPERATURE