Path-integral analysis of bosons interacting with a gauge field

Journal Article · Sun May 01 04:00:00 EDT 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.49.13049· OSTI ID:5007403

Ubbens, M U; Lee, P A ^[1]

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1. Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

We analyze an effective action of bosons moving in a fluctuating gauge field, which describes the motion of the holons in the [ital t]-[ital J] model. The analysis is in terms of a dimensionless coupling constant [ital g][similar to]24[pi][ital t]/[ital J]. We use a path-integral approach, which is a convenient method in the strong-coupling limit [ital g][much gt]1. The effect of the gauge field is to suppress boson loops that enclose a large area, so that the main contribution comes from almost self-retracing paths. By taking a quenched average over the gauge field we are able to derive a renormalized density of states that has a shifted band edge, and that is enhanced near the band edge. We also find an expression for the diamagnetic susceptibility [chi][sub [ital B]], that in the strong-coupling limit varies like [chi][sub [ital B]][similar to]([ital gT])[sup [minus]1], and is suppressed by a factor 0.2[ital g] compared to the weak-coupling limit. The enhanced density of states and the suppression of [chi][sub [ital B]] both imply that Bose condensation is suppressed by the fluctuating gauge field. At lower temperatures the retracing path approximation breaks down, and one has to do a self-consistent calculation to determine [chi][sub [ital B]]. A numerical calculation shows that below [ital T][sub [ital B][ital E]][similar to]0.08[ital T][sub [ital B][ital E]][sup 0] the susceptibility [chi][sub [ital B]][sup SC] diverges exponentially.

• OSTI ID: 5007403
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 49:18; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

665400* -- Quantum Physics Aspects of Condensed Matter-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BOSE-EINSTEIN CONDENSATION
COPPER COMPOUNDS
CRYSTAL MODELS
CUPRATES
ELEMENTARY PARTICLES
ENERGY-LEVEL DENSITY
FEYNMAN PATH INTEGRAL
GAUGE INVARIANCE
HIGH-TC SUPERCONDUCTORS
INTEGRALS
INVARIANCE PRINCIPLES
MAGNETIC PROPERTIES
MAGNETIC SUSCEPTIBILITY
MATHEMATICAL MODELS
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
POSTULATED PARTICLES
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS