arXiv:cond-mat/0502599 · Physical Review Letters

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

Marcos Rigol, Salvatore R. Manmana, A. Muramatsu, Richard T. Scalettar, Rajiv R. P. Singh, Stefan Weßel

Published Nov 14, 2005• 19 citations

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.

DOI: 10.1103/physrevlett.95.218901

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