Broad versus narrow Fano-Feshbach resonances in the BCS-BEC crossover with trapped Fermi atom

S. Simonucci; P. Pieri; G. C. Strinati

doi:10.1209/epl/i2004-10412-2

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Broad versus narrow Fano-Feshbach resonances in the BCS-BEC crossover with trapped Fermi atom

S. Simonucci·P. Pieri·G. C. Strinati

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Abstract

With reference to the broad and narrow Fano-Feshbach resonances of 6Li at about 822 G and 543 G, we show that for the broad resonance a molecular coupled-channel calculation can be mapped with excellent accuracy onto an effective single-channel problem with a contact interaction. This occurs for a wide enough range of the magnetic field, that the full BCS-BEC crossover can be realized with a typical trap. For the narrow resonance, the mapping onto a single-channel problem and the realization of the BCS-BEC crossover are restricted to too narrow a range of the magnetic field to obtain them in practice. In this way, the BCS-BEC crossover for Fermi atoms with the broad resonance is placed on the same footing as the corresponding crossover for different physical systems.

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S. Simonucci, P. Pieri, G. C. Strinati. 2005-01-20. Broad versus narrow Fano-Feshbach resonances in the BCS-BEC crossover with trapped Fermi atom. https://doi.org/10.1209/epl%2Fi2004-10412-2

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