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arXiv · 1612.07716

Many-body Quantum Chaos and Entanglement in a Quantum Ratchet

Marc Andrew Valdez·Gavriil Shchedrin·Martin Heimsoth·Charles E. Creffield·Fernando Sols·Lincoln D. Carr
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Abstract

We uncover signatures of quantum chaos in the many-body dynamics of a Bose-Einstein condensate-based quantum ratchet in a toroidal trap. We propose measures including entanglement, condensate depletion, and spreading over a fixed basis in many-body Hilbert space which quantitatively identify the region in which quantum chaotic many-body dynamics occurs, where random matrix theory is limited or inaccessible. With these tools we show that many-body quantum chaos is neither highly entangled nor delocalized in the Hilbert space, contrary to conventionally expected signatures of quantum chaos.

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Marc Andrew Valdez, Gavriil Shchedrin, Martin Heimsoth, Charles E. Creffield, Fernando Sols, Lincoln D. Carr. 2016-12-22. Many-body Quantum Chaos and Entanglement in a Quantum Ratchet. https://doi.org/10.1103/physrevlett.120.234101

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