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arXiv · 2104.08670

Solution of one-dimensional Bose Hubbard model in large-$U$ limit

Yong Zheng
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Abstract

The one-dimensional Bose-Hubbard model in large-$U$ limit has been studied via reducing and mapping the Hamiltonian to a simpler one. The eigenstates and eigenvalues have been obtained exactly in the subspaces with fixed numbers of single- and double-occupancies but without multiple-occupancies, and the thermodynamic properties of the system have been calculated further. These eigenstates and eigenvalues also enable us to develop a new perturbation treatment of the model, with which the ground-state energy has been calculated exactly to first order in $1/U$.

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Yong Zheng. 2021-04-18. Solution of one-dimensional Bose Hubbard model in large-$U$ limit. https://doi.org/10.7566/jpsj.91.014002

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