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arXiv · 1106.6179

Phase diagram of Landau-Zener phenomena in coupled one-dimensional Bose quantum fluids

Abstract

We study stationary and dynamical properties of the many-body Landau-Zener dynamics of a Bose quantum fluid confined in two coupled one-dimensional chains, using a many-body generalization recently reported [Y.-A. Chen et al.], within the decoupling approximation and the one-level band scheme. The energy spectrum evidences the structure of the avoided level crossings as a function of the on-site inter particle interaction strength. On the dynamical side, a phase diagram of the transfer efficiency across ground-state and inverse sweeps is presented. A totally different scenario with respect to the original single-particle Landau-Zener scheme is found for ground-state sweeps, in which a breakdown of the adiabatic region emerges as the sweep rate decreases. On the contrary, the transfer efficiency across inverse sweeps reveals consistent results with the single-particle Landau-Zener predictions. In the strong coupling regime, we find that there is a critical value of the on-site interaction for which the transfer of particles starts to vanish independently of the sweep rate. Our results are in qualitative agreement with those of the experimental counterpart.

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Santiago F. Caballero-Benitez, Rosario Paredes. 2012-01-19. Phase diagram of Landau-Zener phenomena in coupled one-dimensional Bose quantum fluids. https://doi.org/10.1103/physreva.85.023605

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