Elongated Fermi superfluid: absence of critical imbalance enhancement at equilibrium

Masaki Tezuka; Youichi Yanase; Masahito Ueda

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arXiv · 0811.1650

Elongated Fermi superfluid: absence of critical imbalance enhancement at equilibrium

Masaki Tezuka·Youichi Yanase·Masahito Ueda

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Abstract

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 $λ$, 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 $λ$ 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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Masaki Tezuka, Youichi Yanase, Masahito Ueda. 2010-06-01. Elongated Fermi superfluid: absence of critical imbalance enhancement at equilibrium. https://arxiv.org/abs/0811.1650

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