Nonequilibrium quantum dynamics of partial symmetry breaking for ultracold bosons in an optical lattice ring trap

ORAL

Abstract

We explore the nonequilibrium quantum dynamics of partial symmetry-breaking in ring Bose-Einstein condensates described by the Bose-Hubbard Hamiltonian with an external potential. Using exact diagonalization and group theory for small systems, we establish three new concepts to predict and characterize the dynamics after a quantum quench: symmetry memory, critical symmetry-breaking strength, and the symmetry gap. Critical symmetry breaking can manifest in current reversals, but is most clearly observed in the symmetry memory operator, based on unitary rotations.

*Funded by NSF, AFOSR, AvH Foundation, and MINECO

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Authors

  • Lincoln D. Carr

    • Department of Physics, Colorado School of Mines
    • Colorado School of Mines, Golden, CO, USA and University of Heidelberg, Germany
    • Colorado School of Mines
    • Department of Physics, Colorado School of Mines, Golden, Colorado, USA

  • Miguel Angel Garcia-March

    • Institute of Photonic Sciences and University of Barcelona, Spain

  • Javier Vijande

    • University of Valencia, Spain

  • Albert Ferrando

    • University of Valencia, Spain