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arXiv · 0808.0409

DC Josephson Effect with Fermi gases in the Bose-Einstein regime

F. Ancilotto·L. Salasnich·F. Toigo
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Abstract

We show that the DC Josephson effect with ultracold fermionic gases in the BEC regime of composite molecules can be described by a nonlinear Schrodinger equation (NLSE). By comparing our results with Bogoliubov-de Gennes calculations [Phys. Rev. Lett. 99, 040401 (2007)] we find that our superfluid NLSE, which generalizes the Gross-Pitaevskii equation taking into account the correct equation of state, is reliable in the BEC regime of the BCS-BEC crossover up to the limit of very large (positive) scattering length. We also predict that the Josephson current displays relevant beyond mean-field effects.

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F. Ancilotto, L. Salasnich, F. Toigo. 2008-11-21. DC Josephson Effect with Fermi gases in the Bose-Einstein regime. https://doi.org/10.1103/physreva.79.033627

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