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Measurement of interaction energy near a Feshbach resonance in a 6Li Fermi gas

T. Bourdel·J. Cubizolles·L. Khaykovich·K. M. F. Magalhaes·S. J. J. M. F. Kokkelmans·G. V. Shlyapnikov·C. Salomon
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Abstract

We investigate the strongly interacting regime in an optically trapped $^6$Li Fermi mixture near a Feshbach resonance. The resonance is found at $800(40) $G in good agreement with theory. Anisotropic expansion of the gas is interpreted by collisional hydrodynamics. We observe an unexpected and large shift ($80 $G) between the resonance peak and both the maximum of atom loss and the change of sign of the interaction energy.

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T. Bourdel, J. Cubizolles, L. Khaykovich, K. M. F. Magalhaes, S. J. J. M. F. Kokkelmans, G. V. Shlyapnikov, C. Salomon. 2003-03-05. Measurement of interaction energy near a Feshbach resonance in a 6Li Fermi gas. https://doi.org/10.1103/physrevlett.91.020402

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