Phase Diagram of the Bose Hubbard Model with Weak Links

ORAL

Abstract

We study the ground state phase diagram of strongly interacting ultracold Bose gas in a one-dimensional optical lattice with a tunable weak link, by means of Quantum Monte Carlo simulation. This model contains an on-site repulsive interaction (U) and two different near-neighbor hopping terms, $J$ and $t$, for the weak link and the remainder of the chain, respectively. We show that by reducing the strength of $J$, a novel intermediate phase develops which is compressible and non-superfluid. This novel phase is identified as a Normal Bose Liquid (NBL) which does not appear in the phase diagram of the homogeneous bosonic Hubbard model. Further, we find a linear variation of the phase boundary of Normal Bose Liquid (NBL) to SuperFluid (SF) as a function of the strength of the weak link. These results may provide a new path to design advanced atomtronic devices in the future.

Authors

  • Kalani Hettiarachchilage

    Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA

  • Valery Rousseau

    Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA, Louisiana State University (LSU)

  • Ka-Ming Tam

    Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA, Louisiana State University (LSU), Louisiana State University, Department of Physics and Astronomy, Louisiana State University, Department of Physics \& Astronomy, Louisiana State University

  • Juana Moreno

    Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, USA, Louisiana State University, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, Department of Physics and Astronomy, Louisiana State University, Department of Physics \& Astronomy, Louisiana State University

  • Mark Jarrell

    Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, USA, Louisiana State University, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, Louisiana State University (LSU), Department of Physics and Astronomy, Louisiana State University, Department of Physics \& Astronomy, Louisiana State University

  • Daniel Sheehy

    Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA, Louisiana State University