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arXiv · 0809.0505

Metastable superfluidity of repulsive fermionic atoms in optical lattices

Achim Rosch·David Rasch·Benedikt Binz·Matthias Vojta
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Abstract

In the fermionic Hubbard model, doubly occupied states have an exponentially large lifetime for strong repulsive interactions U. We show that this property can be used to prepare a metastable s-wave superfluid state for fermionic atoms in optical lattices described by a large-U Hubbard model. When an initial band-insulating state is expanded, the doubly occupied sites Bose condense. A mapping to the ferromagnetic Heisenberg model in an external field allows for a reliable solution of the problem. Nearest-neighbor repulsion and pair hopping are important in stabilizing superfluidity.

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Achim Rosch, David Rasch, Benedikt Binz, Matthias Vojta. 2008-12-29. Metastable superfluidity of repulsive fermionic atoms in optical lattices. https://doi.org/10.1103/physrevlett.101.265301

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