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arXiv · 1108.4851

Improved variational approach to the two-site Bose-Hubbard model

Marina Melé-Messeguer·Bruno Juliá-Díaz·Artur Polls
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Abstract

An improved variational ansatz is proposed to capture the most striking properties of the ground state of a slightly biased attractive two-site Bose-Hubbard Hamiltonian. Our ansatz, albeit its simplicity, is found to capture well the exact properties of the ground state for a wide variety of model parameters, in particular the fragmentation occurring before the formation of cat-like states and also the formation of strongly correlated cat-like states.

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Marina Melé-Messeguer, Bruno Juliá-Díaz, Artur Polls. 2011-08-24. Improved variational approach to the two-site Bose-Hubbard model. https://doi.org/10.1007/s10909-011-0395-4

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