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arXiv · 1810.02772

Analytical Pendulum Model for a Bosonic Josephson Junction

Marine Pigneur·Jörg Schmiedmayer
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Abstract

We present an analytical description of the tunneling dynamics between two coupled Bose-Einstein condensates in the Josephson regime. The model relies on the classical analogy with a rigid pendulum and focuses on two dynamical modes of this system: Josephson oscillations and Macroscopic Quantum Self-Trapping. The analogy is extended to include an energy difference between the two superfluids caused by an asymmetry in the trapping potential. The model is compatible with the mean-field predictions of the two-mode Bose-Hubbard model. It gives new insights on the mean-field model by involving experimentally measurable parameters with reduced correlations. For agreement with recent experimental observations, we establish heuristic formulas including a dissipation. We conclude with a convincing application of the model to several sets of experimental results.

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Marine Pigneur, Jörg Schmiedmayer. 2018-10-05. Analytical Pendulum Model for a Bosonic Josephson Junction. https://doi.org/10.1103/physreva.98.063632

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