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arXiv · 0906.4378

A Universal Trimer in a Three-Component Fermi Gas

Abstract

We show that the recently measured magnetic field dependence of three-body loss in a three-component mixture of ultracold $^6$Li atoms [1,2] can be explained by the presence of a universal trimer state. Previous work suggested a universal trimer state as a probable explanation, yet failed to get good agreement between theory and experiment over the whole range of magnetic fields. For our description we adapt the theory of Braaten and Hammer [3] for three identical bosons to the case of three distinguishable fermions by combining the three scattering lengths $a_{12},$ $a_{23}$ and $a_{13}$ between the three components to an effective interaction parameter $a_m$. We show that taking into account a magnetic field variation of the lifetime of the trimer state is essential to obtain a complete understanding of the observed decay rates.

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A. N. Wenz, T. Lompe, T. B. Ottenstein, F. Serwane, G. Zürn, S. Jochim. 2009-11-24. A Universal Trimer in a Three-Component Fermi Gas. https://doi.org/10.1103/physreva.80.040702

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