Microscopic theory of the lambda transition

Journal Article · Tue Jun 01 04:00:00 EDT 1982 · Ann. Phys. (N.Y.); (United States)

DOI:https://doi.org/10.1016/0003-4916(82)90277-9· OSTI ID:5043837

Toyoda, T

Starting with a microscopic hamiltonian for a many-boson system with a hardcore interaction, the grand potential of the system, which contains the order-parameter of the lambda transition as one of the thermodynamical variables, is derived by making use of the finite temperature loop expansion. The divergence difficulty caused by the hardcore interaction is circumvented by the conventional field theoretic perturbation renormalization such that the chemical potential is renormalized instead of the conventional mass renormalization. The grand potential obtained consists of the superfluid part and the finite temperature elementary excitation part. The elementary excitation energy spectrum shows the Goldstone boson mode, namely, the photon, for the zero external field. A non-vanishing external field destroys such a Goldstone boson mode by causing an energy gap at zero momentum. The chemical potential and the critical temperature are also obtained for the weak coupling case. It is shown how the Bose-Einstein condensation is affected by the hardcore interaction.

• Research Organization: Institut fuer Theoretische Physik der Universitaet Tuebingen, Auf der Morgenstelle 14, 7400 Tuebingen 1, Federal Republic of Germany
• OSTI ID: 5043837
• Journal Information: Ann. Phys. (N.Y.); (United States), Journal Name: Ann. Phys. (N.Y.); (United States) Vol. 141:1; ISSN APNYA
• Country of Publication: United States
• Language: English

Related Subjects

640450* -- Fluid Physics-- Superfluidity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BOSE-EINSTEIN CONDENSATION
BOSONS
ELEMENTARY PARTICLES
EVEN-EVEN NUCLEI
FUNCTIONS
GOLDSTONE BOSONS
HAMILTONIANS
HELIUM 4
HELIUM ISOTOPES
ISOTOPES
LAMBDA POINT
LIGHT NUCLEI
MATHEMATICAL OPERATORS
NUCLEI
ORDER PARAMETERS
PARTITION FUNCTIONS
PHYSICAL PROPERTIES
POSTULATED PARTICLES
QUANTUM OPERATORS
RENORMALIZATION
STABLE ISOTOPES
SUPERFLUIDITY
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE