Condensate fluctuations of interacting Bose gases within a microcanonical ensemble

Journal Article · Sun May 15 04:00:00 EDT 2011 · Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print)

DOI:https://doi.org/10.1103/PHYSREVE.83.051132· OSTI ID:21560283

Jianhui, Wang; Jizhou, He; Yongli, Ma ^[1]

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1. Department of Physics, Nanchang University, Nanchang 330031 (China)

Based on counting statistics and Bogoliubov theory, we present a recurrence relation for the microcanonical partition function for a weakly interacting Bose gas with a finite number of particles in a cubic box. According to this microcanonical partition function, we calculate numerically the distribution function, condensate fraction, and condensate fluctuations for a finite and isolated Bose-Einstein condensate. For ideal and weakly interacting Bose gases, we compare the condensate fluctuations with those in the canonical ensemble. The present approach yields an accurate account of the condensate fluctuations for temperatures close to the critical region. We emphasize that the interactions between excited atoms turn out to be important for moderate temperatures.

• OSTI ID: 21560283
• Journal Information: Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print), Journal Name: Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print) Journal Issue: 5 Vol. 83; ISSN 1539-3755
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATOMS
BOSE-EINSTEIN CONDENSATION
BOSE-EINSTEIN GAS
COMPARATIVE EVALUATIONS
DISTRIBUTION FUNCTIONS
ENERGY LEVELS
EVALUATION
EXCITED STATES
FLUCTUATIONS
FUNCTIONS
MATHEMATICS
PARTICLES
PARTITION FUNCTIONS
STATISTICS
VARIATIONS