Population imbalance and pairing in the BCS-BEC crossover of three-component ultracold fermions

doi:https://doi.org/10.1103/PHYSREVA.82.063615

Title: Population imbalance and pairing in the BCS-BEC crossover of three-component ultracold fermions

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Abstract

We investigate the phase diagram and the BCS-BEC crossover of a homogeneous three-component ultracold Fermi gas with a U(3)-invariant attractive interaction. We show that the system at sufficiently low temperatures exhibits population imbalance as well as fermionic pairing. We describe the crossover in this system, connecting the weakly interacting BCS regime of the partially population-imbalanced fermion pairing state and the BEC limit with three weakly interacting species of molecules, including pairing fluctuations within a t-matrix calculation of the particle self-energies.

Authors:

Ozawa, Tomoki; Baym, Gordon ^[1]

Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801 (United States)

Publication Date:: 2010-12-15

OSTI Identifier:: 21528938

Resource Type:: Journal Article

Journal Name:: Physical Review. A

Additional Journal Information:: Journal Volume: 82; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.82.063615; (c) 2010 American Institute of Physics; Journal ID: ISSN 1050-2947

Country of Publication:: United States

Language:: English

Subject:: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; BOSE-EINSTEIN CONDENSATION; FERMI GAS; FERMIONS; FLUCTUATIONS; MOLECULES; PAIRING INTERACTIONS; PHASE DIAGRAMS; S MATRIX; SELF-ENERGY; TEMPERATURE RANGE 0065-0273 K; DIAGRAMS; ENERGY; INFORMATION; INTERACTIONS; MATRICES; TEMPERATURE RANGE; VARIATIONS

Citation Formats


                    Ozawa, Tomoki, and Baym, Gordon. Population imbalance and pairing in the BCS-BEC crossover of three-component ultracold fermions.  United States: N. p., 2010. 
        Web.  doi:10.1103/PHYSREVA.82.063615.

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                    Ozawa, Tomoki, & Baym, Gordon. Population imbalance and pairing in the BCS-BEC crossover of three-component ultracold fermions.  United States.  https://doi.org/10.1103/PHYSREVA.82.063615

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                    Ozawa, Tomoki, and Baym, Gordon. Wed .  
        "Population imbalance and pairing in the BCS-BEC crossover of three-component ultracold fermions".  United States.  https://doi.org/10.1103/PHYSREVA.82.063615.

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@article{osti_21528938,

  title        = {Population imbalance and pairing in the BCS-BEC crossover of three-component ultracold fermions},

  author       = {Ozawa, Tomoki and Baym, Gordon},

  abstractNote = {We investigate the phase diagram and the BCS-BEC crossover of a homogeneous three-component ultracold Fermi gas with a U(3)-invariant attractive interaction. We show that the system at sufficiently low temperatures exhibits population imbalance as well as fermionic pairing. We describe the crossover in this system, connecting the weakly interacting BCS regime of the partially population-imbalanced fermion pairing state and the BEC limit with three weakly interacting species of molecules, including pairing fluctuations within a t-matrix calculation of the particle self-energies.},

  doi          = {10.1103/PHYSREVA.82.063615},

  url          = {https://www.osti.gov/biblio/21528938},
  journal      = {Physical Review. A},

  issn         = {1050-2947},

  number       = 6,

  volume       = 82,

  place        = {United States},

  year         = {2010},

  month        = {12}

}

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