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arXiv · 2007.10901

Capturing the Feshbach-induced Pairing Physics in the BEC-BCS Crossover

Eloisa Cuestas·José I. Robledo·Ana P. Majtey
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Abstract

By including the effect of a trap with characteristic energy given by the Fermi temperature $T_F$ in a two-body two-channel model for Feshbach resonances, we reproduce the experimental closed-channel fraction $Z$ across the BEC-BCS crossover and into the BCS regime of a $^6$Li atomic Fermi gas. We obtain the expected behavior $Z \propto \sqrt{T_F}$ at unitarity, together with the recently measured proportionality constant. Our results are also in agreement with recent measurements of the $Z$ dependency on $T_F$ on the BCS side, where a significant discrepancy between experiments and theory has been repeatedly reported.

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Eloisa Cuestas, José I. Robledo, Ana P. Majtey. 2020-07-21. Capturing the Feshbach-induced Pairing Physics in the BEC-BCS Crossover. https://arxiv.org/abs/2007.10901

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