Simple model for the quasiparticle interactions in /sup 3/He. II. Transport coefficients and the superfluid free energy
We explore the consequences of a phenomenological model for the low-frequency interaction (vertex function) in /sup 3/He of the form GAMMA/sup k/ approx.-J (q) S x S + V (q). Here q represents the magnitude of the momentum and energy transfer. This is the second in a series of two papers and is concerned primarily with transport properties and the superfluid free energy. In the first paper we demonstrated that for spin-fluctuation-like models, in which J is peaked at q = 0 and V is relatively small, we obtain good agreement between theory and experiment for the magnitude and pressure dependence of the superfluid transition temperature. In the present paper we show that these spin-fluctuation-like models yield reasonably good agreement with the measured zero-temperature transport coefficients at all pressures. They, therefore, represent a considerably better description of the high-pressure scattering amplitudes than the s-p approximation. The five fourth-order superfluid Landau-Ginzburg free-energy invariants, ..beta../sub i/, are computed using the Ranier-Serene formalism. At high and low pressures, paramagnonlike theories yield results essentially equivalent to those obtained in the s-p approximation. As in all previous calculations, while the combination ..beta../sub 2/ + ..beta../sub 4/ is in nearly exact agreement with high-pressure data, vertical-bar ..beta../sub 5/ vertical-bar is about 30% too large. We have also considered models for GAMMA/sup k/ in which J is of the spin-density wave form and in which J = 0. In both these cases the transport coefficients and the ..beta../sub i/ are inconsistent with experiment. The evidence strongly suggests that it is the proximity to the ferromagnetic instability which governs the behavior of the scattering amplitudes in /sup 3/He and all properties derived from them.
- Research Organization:
- Department of Physics and The James Franck Institute, The University of Chicago, Chicago, Illinois 60637
- OSTI ID:
- 6092183
- Journal Information:
- Phys. Rev., B: Condens. Matter; (United States), Vol. 20:1
- Country of Publication:
- United States
- Language:
- English
Similar Records
Specific heat of normal and superfluid /sup 3/He
Strong coupling corrections to the Ginzburg-Landau theory of superfluid {sup 3}He
Related Subjects
SUPERCONDUCTIVITY AND SUPERFLUIDITY
HELIUM 3
FREE ENERGY
QUASI PARTICLES
SUPERFLUIDITY
GINZBURG-LANDAU THEORY
PRESSURE DEPENDENCE
TRANSPORT THEORY
VERTEX FUNCTIONS
ENERGY
EVEN-ODD NUCLEI
FUNCTIONS
HELIUM ISOTOPES
ISOTOPES
LIGHT NUCLEI
NUCLEI
PHYSICAL PROPERTIES
STABLE ISOTOPES
THERMODYNAMIC PROPERTIES
640450* - Fluid Physics- Superfluidity