arXiv:1112.5013 · Physical Review A

Entangling many-body bound states with propagative modes in Bose-Hubbard systems

Mario Collura, Helge Aufderheide, Guillaume Roux, Dragi Karevski

Published Jul 12, 2012• 45 citations

Abstract

The quantum evolution of a cloud of bosons initially localized on part of a one-dimensional optical lattice and suddenly subjected to a linear ramp is studied, realizing a quantum analog of the ``Galileo ramp'' experiment. The main remarkable effects of this realistic setup are revealed using analytical and numerical methods. Only part of the particles are ejected for a high enough ramp, while the others remain self-trapped. Then, the trapped density profile displays rich dynamics with Josephson-type oscillations around a plateau. This setup, by coupling bound states to propagative modes, creates two diverging condensates for which the entanglement is computed and related to the equilibrium one. Further, we address the role of integrability on the entanglement and on the damping and thermalization of simple observables.

DOI: 10.1103/physreva.86.013615

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