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Atom-molecule theory of broad Feshbach resonances

G. M. Falco·H. T. C. Stoof
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Abstract

We derive the atom-molecule theory for an atomic gas near a broad Feshbach resonance, where the energy dependence of the atom-molecule coupling becomes crucial for understanding experimental results. We show how our many-body theory incorporates the two-atom physics exactly. In particular, we calculate the magnetic moment of a two-component gas of ^{6}Li atoms for a wide range of magnetic fields near the broad Feshbach resonance at about 834 Gauss. We find excellent agreement with the experiment of Jochim et al. [Phys. Rev. Lett. 91, 240402 (2003)].

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G. M. Falco, H. T. C. Stoof. 2004-09-23. Atom-molecule theory of broad Feshbach resonances. https://doi.org/10.1103/physreva.71.063614

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