Stability of Superflow for Ultracold Fermions in Optical Lattices
Stability of Superflow for Ultracold Fermions in Optical Lattices
We investigate the stability of superflow of paired fermions in an optical lattice. We show that there are two distinct dynamical instabilities which limit the superflow in this system. One dynamical instability occurs when the superfluid stiffness becomes negative; this evolves, with increasing pairing interaction, from the fermion pair breaking …