Criticality and superfluidity in a dilute Bose fluid

Journal Article · Tue Apr 01 04:00:00 EST 1986 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.33.4632· OSTI ID:6056718

Weichman, P B; Rasolt, M; Fisher, M E; Stephen, M J

The crossover from ideal-Bose-gas behavior to nonclassical, XY-like criticality in a dilute, interacting Bose fluid is considered in detail with emphasis on the superfluid density, rho/sub s/(T), below the transition. A general discussion of crossover scaling in constrained systems shows that rho/sub s/ and other temperature-dependent thermodynamic functions at controlled overall density can be expressed in terms of universal scaling functions. The finite-temperature Green's function formalism is used to calculate the associated linear scaling fields and the crossover exponent exactly for all dimensionalities d>2, scaling predictions, including logarithmic singularities just at d = 3, being checked via second-order computations. A mapping of the Bose problem onto the classical s/sup 4/ spin model is achieved which is asymptotically exact in the critical region. In this way, previously known renormalization-group results are used to calculate the scaling functions for rho/sub s/, for the off-diagonal susceptibility, etc., to first order in epsilon = 4-d. Good agreement is found with the experimental measurements by Reppy and co-workers of rho/sub s/(T) for helium absorbed at low coverages in Vycor glass (of pore size 50--80 A). An effective-mass ratio m(/mapprox. =1.5, and an effective-scattering-length ratio a(/aapprox. =1.3 are indicated for mobile helium in the Vycor (although the irregular character of Vycor has not, at this point, been fully allowed for in the theory).

• Research Organization: Baker Laboratory, Cornell University, Ithaca, New York 14853
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 6056718
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 33:7; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

640450* -- Fluid Physics-- Superfluidity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ADSORPTION
BOSE-EINSTEIN CONDENSATION
BOSE-EINSTEIN GAS
DENSITY
EVEN-EVEN NUCLEI
GLASS
HELIUM 4
HELIUM ISOTOPES
ISOTOPES
LIGHT NUCLEI
NUCLEI
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
SCALING LAWS
SORPTION
STABLE ISOTOPES
SUPERFLUIDITY
THERMODYNAMIC PROPERTIES