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arXiv · 1507.06426

Properties of the one-dimensional Bose-Hubbard model from a high-order perturbative expansion

Bogdan Damski·Jakub Zakrzewski
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Abstract

We employ a high-order perturbative expansion to characterize the ground state of the Mott phase of the one-dimensional Bose-Hubbard model. We compute for different integer filling factors the energy per lattice site, the two-point and density-density correlations, and expectation values of powers of the on-site number operator determining the local atom number fluctuations (variance, skewness, kurtosis). We compare these expansions to numerical simulations of the infinite-size system to determine their range of applicability. We also discuss a new sum rule for the density-density correlations that can be used in both equilibrium and non-equilibrium systems.

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Bogdan Damski, Jakub Zakrzewski. 2015-07-23. Properties of the one-dimensional Bose-Hubbard model from a high-order perturbative expansion. https://doi.org/10.1088/1367-2630%2F17%2F12%2F125010

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