Quantum Phase Transitions of Ultra Cold Gases in the Fermi-Bose Hubbard Hamiltonian

ORAL

Abstract

The experimental realization of ultracold fermions has stimulated work on theoretical models of zero-temperature quantum phase transitions and the BCS-BEC crossover. Ultracold gases confined in optical lattices can demonstrate a wide range of different phases by varying controllable system parameters, such as optical lattice intensity, particle number, spin composition and atomic interactions. We perform numerical studies of a Fermi-Bose-Hubbard Hamiltonian with the Vidal algorithm (Time Evolving Block Decimation). Our Hamiltonian treats a one dimensional system of fermions coupled to a bosonic molecular state, as occurs in Feshbach resonances, and encompasses a very large parameter space. We present the quantum phase diagram, focusing on small systems and the most experimentally relevant parameters.

*We gratefully acknowledge the National Science Foundation for support.

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Authors

  • D. G. Schirmer

    • Colorado School of Mines

  • L. D. Carr

    • Physics Department, Colorado School of Mines
    • Dept. of Physics, Colorado School of Mines, Golden, CO 80401 USA
    • Physics Department, Colorado School of Mines, Golden, CO, 80401
    • Colorado School of Mines
    • Physics Department, Colorado School of Mines, Golden, CO 80401
    • Physics Department, Colorado School of Mines, Golden, CO, USA
    • Physics Department, Colorado School of Mines, Golden, Colorado 80401, USA

  • I. Danshita

    • National Institute for Standards and Technology

  • J.E. Williams

    • National Institute for Standards and Technology

  • Charles Clark

    • National Institute for Standards and Technology