Fermion pairing with spin-density imbalance in an optical lattice
Superconductivity
2007-05-23 v2 Materials Science
Abstract
We consider pairing in a two-component atomic Fermi gas, in a three-dimensional optical lattice, when the components have unequal densities, i.e. the gas is polarized. We show that a superfluid where the translational symmetry is broken by a finite Cooper pair momentum, namely an FFLO-type state, minimizes the Helmholtz free energy of the system. We demonstrate that such a state is clearly visible in the observable momentum distribution of the atoms, and analyze the dependence of the order parameter and the momentum distribution on the filling fraction and the interaction strength.
Keywords
Cite
@article{arxiv.cond-mat/0605169,
title = {Fermion pairing with spin-density imbalance in an optical lattice},
author = {T. Koponen and J. Kinnunen and J. -P. Martikainen and L. M. Jensen and P. Torma},
journal= {arXiv preprint arXiv:cond-mat/0605169},
year = {2007}
}
Comments
18 pages, 17 figures, replaced with published version, also available at http://stacks.iop.org/1367-2630/8/179