Superfluid-insulator transition in a moving system of interacting bosons.

  title={Superfluid-insulator transition in a moving system of interacting bosons.},
  author={Ehud Altman and Anatoli S. Polkovnikov and Eugene A. Demler and Bertrand I Halperin and Mikhail D Lukin},
  journal={Physical review letters},
  volume={95 2},
We analyze the stability of superfluid currents in a system of strongly interacting ultracold atoms in an optical lattice. We show that such a system undergoes a dynamic, irreversible phase transition at a critical phase gradient that depends on the interaction strength between atoms. At commensurate filling, the phase boundary continuously interpolates between the classical modulation instability of a weakly interacting condensate and the equilibrium quantum phase transition into a Mott… CONTINUE READING