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arXiv · 0709.2386

The one-dimensional Bose-Fermi-Hubbard model in the heavy-fermion limit

A. Mering·M. Fleischhauer
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Abstract

We study the phase diagram of the zero-temperature, one-dimensional Bose-Fermi-Hubbard model for fixed fermion density in the limit of small fermionic hopping. This model can be regarded as an instance of a disordered Bose-Hubbard model with dichotomic values of the stochastic variables. Phase boundaries between compressible, incompressible (Mott-insulating) and partially compressible phases are derived analytically within a generalized strong-coupling expansion and numerically using density matrix renormalization group (DMRG) methods. We show that first-order correlations in the partially compressible phases decay exponentially, indicating a glass-type behaviour. Fluctuations within the respective incompressible phases are determined using perturbation theory and are compared to DMRG results.

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A. Mering, M. Fleischhauer. 2007-10-08. The one-dimensional Bose-Fermi-Hubbard model in the heavy-fermion limit. https://doi.org/10.1103/physreva.77.023601

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