Resonant Superfluidity in an Optical Lattice
Abstract
We study a system of ultracold fermionic Potassium (40K) atoms in a three-dimensional optical lattice in the vicinity of an s-wave Feshbach resonance. Close to resonance, the system is described by a multi-band Bose-Fermi Hubbard Hamiltonian. We derive an effective lowest-band Hamiltonian in which the effect of the higher bands is incorporated by a self-consistent mean-field approximation. The resulting model is solved by means of Generalized Dynamical Mean-Field Theory. In addition to the BEC/BCS crossover we find a phase transition to a fermionic Mott insulator at half filling, induced by the repulsive fermionic background scattering length. We also calculate the critical temperature of the BEC/BCS-state and find it to be minimal at resonance.
Cite
@article{arxiv.0912.1589,
title = {Resonant Superfluidity in an Optical Lattice},
author = {I. Titvinidze and M. Snoek and W. Hofstetter},
journal= {arXiv preprint arXiv:0912.1589},
year = {2010}
}
Comments
19 pages, 3 figures