Thermal and quantum fluctuations of confined Bose–Einstein condensate beyond the Bogoliubov approximation

Journal Article · Sun Jan 15 00:00:00 EST 2017 · Annals of Physics

DOI:https://doi.org/10.1016/J.AOP.2016.12.020· OSTI ID:22617460

Nakamura, Y., E-mail: [e-mail] ^[1]; Nagano Prefectural Kiso Seiho High School, Nagano 397-8571 ^[2]; Kawaguchi, T., E-mail: [e-mail] ^[1]; Torii, Y., E-mail: [e-mail] ^[1]; Yamanaka, Y., E-mail: [e-mail] ^[1]

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1. Department of Electronic and Physical Systems, Waseda University, Tokyo 169-8555 (Japan)
2. (Japan)

The formulation for zero mode of a Bose–Einstein condensate beyond the Bogoliubov approximation at zero temperature [Y. Nakamura et al., Phys. Rev. A 89 (2014) 013613] is extended to finite temperature. Both thermal and quantum fluctuations are considered in a manner consistent with a concept of spontaneous symmetry breakdown for a finite-size system. Therefore, we need a proper treatment of the zero mode operators, which invoke non-trivial enhancements in depletion condensate and thermodynamical quantities such as the specific heat. The enhancements are visible in the weak interaction case. Our approach reproduces the results of a homogeneous system in the Bogoliubov approximation in a large particle number limit.

• OSTI ID: 22617460
• Journal Information: Annals of Physics, Vol. 376; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-4916
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
APPROXIMATIONS
BOSE-EINSTEIN CONDENSATION
FLUCTUATIONS
QUANTUM FIELD THEORY
SPECIFIC HEAT
SYMMETRY BREAKING
WEAK INTERACTIONS
FUNDAMENTAL INTERACTIONS