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arXiv:0709.2386 · Physical Review A

One-dimensional Bose-Fermi-Hubbard model in the heavy-fermion limit

Alexander Mering, Michael Fleischhauer

Published Feb 1, 2008• 52 citations
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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 behavior. Fluctuations within the respective incompressible phases are determined using perturbation theory and are compared to DMRG results.

DOI
10.1103/physreva.77.023601

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