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تسجيل مستخدم جديدElongated Fermi superfluid: absence of critical imbalance enhancement at equilibrium
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We show that the maximum population imbalance ratio $P_mathrm{CC}$ for a two-component Fermi gas near the unitarity limit to condense does not increase with the trap aspect ratio $lambda$, by two methods of 1) solving the Bogoliubov-de Gennes equations with coupling-constant renormalization, and 2) studying the pairing susceptibility by the real-space self-consistent $T$-matrix approximation. The deviation of the cloud shape from what is expected from the trap shape increases but stays minor with increasing $lambda$ up to 50. This finding indicates that despite the apparent discrepancy between the MIT and Rice experiments over the value of $P_mathrm{CC}$ and the validity of local density approximation, the equilibrium state of the system for the aspect ratio in the Rice experiment should be consistent with that of MIT.
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