Superfluid sup 3 He in confined geometries

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6046114

Ullah, S

Superfluid {sup 3}He is a fermionic superfluid with a critical temperature {Tc}{approx} 1 mK. In this thesis the author describes some of the experimentally observable effects of confining superfluid {sup 3}He on scales of the order of the coherence length {xi} {approx} 60 nm. The Ginzburg-Landau theory is used throughout, so the results are valid near {Tc} only. The introduction discusses the various theoretical approaches to understanding superfluid {sup 3}He and considers the position of the Ginzburg-Landau theory in the hierarchy of theories of fermionic superfluidity. Chapter 2 deals with the calculation of critical currents and the modification of the phase diagram of superfluid {sup 3}He in narrow pores and thin slabs. In chapter 3 he derives the magnetic resonance (NMR) frequencies of superfluid {sup 3}He in thin slabs: he finds that NMR can be a very sensitive experimental probe of the order parameter in severely confined geometries. Finally, chapter 4 addresses the problem of the flow of superfluid {sup 3}He-B through a constriction (a weak link) separating two bulk regions of superfluid. He argues that the boundary conditions that describe the applied flow (specified phase gradient) at the bulk ends differ from the analogous situation in a superconducting weak link (specified phase difference).

• Research Organization: Stanford Univ., CA (USA)
• OSTI ID: 6046114
• Country of Publication: United States
• Language: English

Related Subjects

640450* -- Fluid Physics-- Superfluidity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CONFINEMENT
CRITICAL CURRENT
CRITICAL TEMPERATURE
CURRENTS
DIAGRAMS
ELECTRIC CONDUCTIVITY
ELECTRIC CURRENTS
ELECTRICAL PROPERTIES
EVEN-ODD NUCLEI
FLUID FLOW
GINZBURG-LANDAU THEORY
HELIUM 3
HELIUM 3 B
HELIUM ISOTOPES
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MODIFICATIONS
NUCLEAR MAGNETIC RESONANCE
NUCLEI
PHASE DIAGRAMS
PHYSICAL PROPERTIES
RESONANCE
STABLE ISOTOPES
SUPERCONDUCTIVITY
SUPERFLUIDITY
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE