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arXiv · 1503.07885

Bethe states for the two-site Bose-Hubbard model: a binomial approach

Gilberto Santos·Changrim Ahn·Angela Foerster·Itzhak Roditi
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Abstract

We calculate explicitly the Bethe vectors states by the algebraic Bethe ansatz method with the $gl(2)$-invariant $R$-matrix for the two-site Bose-Hubbard model. Using a binomial expansion of the n-th power of a sum of two operators we get and solve a recursion equation. We calculate the scalar product and the norm of the Bethe vectors states. The form factors of the imbalance current operator are also computed.

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Gilberto Santos, Changrim Ahn, Angela Foerster, Itzhak Roditi. 2015-05-19. Bethe states for the two-site Bose-Hubbard model: a binomial approach. https://doi.org/10.1016/j.physletb.2015.05.003

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