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arXiv · 0711.3230

Many-body Landau-Zener tunneling in the Bose-Hubbard model

Andrea Tomadin·Riccardo Mannella·Sandro Wimberger
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Abstract

We study a model for ultracold, spinless atoms in quasi-one dimensional optical lattices and subjected to a tunable tilting force. Statistical tests are employed to quantitatively characterize the spectrum of the Floquet-Bloch operator of the system along the transition from the regular to the quantum chaotic regime. Moreover, we perturbatively include the coupling of the one-band model to the second energy band. This allows us to study the Landau-Zener interband tunneling within a truly many-body description of ultracold atoms. The distributions of the computed tunneling rates provide an independent and experimentally accessible signature of the regular-chaotic transition.

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Andrea Tomadin, Riccardo Mannella, Sandro Wimberger. 2007-11-20. Many-body Landau-Zener tunneling in the Bose-Hubbard model. https://doi.org/10.1103/physreva.77.013606

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