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Quantum Dynamics of Coupled Bosonic Wells within the Bose-Hubbard Picture

R. Franzosi·V. Penna·R. Zecchina
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Abstract

We relate the quantum dynamics of the Bose-Hubbard model (BHM) to the semiclassical nonlinear equations that describe an array of interacting Bose condensates by implementing a standard variational procedure based on the coherent state method. We investigate the dynamics of the two-site BHM from the purely quantum viewpoint by recasting first the model within a spin picture and using then the related dynamical algebra. The latter allows us to study thoroughly the energy spectrum structure and to interpret quantally the classical symmetries of the two-site dynamics. The energy spectrum is also evaluated through various approximations relying on the coherent state approach.

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R. Franzosi, V. Penna, R. Zecchina. 2002-05-10. Quantum Dynamics of Coupled Bosonic Wells within the Bose-Hubbard Picture. https://doi.org/10.1142/s0217979200001011

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