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Quantum dynamics of a model for two Josephson-coupled Bose--Einstein condensates

A. P. Tonel·J. Links·A. Foerster
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Abstract

In this work we investigate the quantum dynamics of a model for two single-mode Bose--Einstein condensates which are coupled via Josephson tunneling. Using direct numerical diagonalisation of the Hamiltonian, we compute the time evolution of the expectation value for the relative particle number across a wide range of couplings. Our analysis shows that the system exhibits rich and complex behaviours varying between harmonic and non-harmonic oscillations, particularly around the threshold coupling between the delocalised and self-trapping phases. We show that these behaviours are dependent on both the initial state of the system as well as regime of the coupling. In addition, a study of the dynamics for the variance of the relative particle number expectation and the entanglement for different initial states is presented in detail.

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A. P. Tonel, J. Links, A. Foerster. 2004-12-21. Quantum dynamics of a model for two Josephson-coupled Bose--Einstein condensates. https://doi.org/10.1088/0305-4470/38/6/004

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