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Mean-field phase diagram for Bose-Hubbard Hamiltonians with random hopping

P. Buonsante·F. Massel·V. Penna·A. Vezzani
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Abstract

The zero-temperature phase diagram for ultracold Bosons in a random 1D potential is obtained through a site-decoupling mean-field scheme performed over a Bose-Hubbard (BH) Hamiltonian whose hopping term is considered as a random variable. As for the model with random on-site potential, the presence of disorder leads to the appearance of a Bose-glass phase. The different phases -i.e. Mott insulator, superfluid, Bose-glass- are characterized in terms of condensate fraction and superfluid fraction. Furthermore, the boundary of the Mott lobes are related to an off-diagonal Anderson model featuring the same disorder distribution as the original BH Hamiltonian.

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P. Buonsante, F. Massel, V. Penna, A. Vezzani. 2006-11-02. Mean-field phase diagram for Bose-Hubbard Hamiltonians with random hopping. https://doi.org/10.1134/s1054660x07040378

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