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arXiv · 2206.09371

Chaos assisted many-body tunnelling

Urbashi Satpathi·Sayak Ray·Amichay Vardi
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Abstract

We study the interplay of chaos and tunnelling between two weakly-coupled Bose-Josephson junctions. The classical phase space of the composite system has a mixed structure including quasi-integrable self-trapping islands for particles and excitations, separated by a chaotic sea. We show that the many-body dynamical tunnelling gap between macroscopic Schr\"odinger cat states supported by these islands is chaos-enhanced. The many-body tunnelling rate fluctuates over several orders of magnitude with small variations of the system parameters or the particle number.

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Urbashi Satpathi, Sayak Ray, Amichay Vardi. 2022-06-19. Chaos assisted many-body tunnelling. https://doi.org/10.1103/physreve.106.l042204

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