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arXiv · 0908.0789

Evidence for Ground- and Excited-State Efimov Trimers in a Three-State Fermi Gas

J. R. Williams·E. L. Hazlett·J. H. Huckans·R. W. Stites·Y. Zhang·K. M. O'Hara
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Abstract

We observe enhanced three-body recombination in an ultracold three-component $^6$Li Fermi gas with large but unequal scattering lengths attributable to an excited Efimov trimer state near the three-atom scattering threshold. We find excellent agreement between the measured three-body recombination rate and the recombination rate calculated in the zero-range approximation where the only free parameters are the Efimov parameters $\kappa_*$ and $\eta_*$. The value of $\kappa_*$ determined by the location of the Efimov resonance we observe at 895 G also predicts the locations of loss features previously observed near 130 and 500 G \cite{Jochim08,OHara09} suggesting that all three features are associated with universal Efimov trimer states. We also report on the first realization of a quantum degenerate three-state Fermi gas with approximate SU(3) symmetry.

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J. R. Williams, E. L. Hazlett, J. H. Huckans, R. W. Stites, Y. Zhang, K. M. O'Hara. 2009-08-06. Evidence for Ground- and Excited-State Efimov Trimers in a Three-State Fermi Gas. https://doi.org/10.1103/physrevlett.103.130404

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