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Comment on "Novel Superfluidity in a Trapped Gas of Fermi Atoms with Repulsive Interaction Loaded on an Optical Lattice"

M. Rigol·S. R. Manmana·A. Muramatsu·R. T. Scalettar·R. R. P. Singh·S. Wessel
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Abstract

In a recent letter Machida et al. [Phys. Rev. Lett. 93, 200402 (2004)] concluded that in a trapped gas of fermions with repulsive interactions a superfluid phase appears around the Mott-insulator at the center of the trap. They base their conclusion on a negative binding energy, and a large weight for a singlet formed by particles located at opposite sides of the Mott-insulator. We show here that the observed effects are not related to superfluidity.

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M. Rigol, S. R. Manmana, A. Muramatsu, R. T. Scalettar, R. R. P. Singh, S. Wessel. 2005-11-15. Comment on "Novel Superfluidity in a Trapped Gas of Fermi Atoms with Repulsive Interaction Loaded on an Optical Lattice". https://doi.org/10.1103/physrevlett.95.218901

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