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Band insulator to Mott insulator transition in a bilayer Hubbard model

S. S. Kancharla·S. Okamoto
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Abstract

The ground state phase diagram of the half-filled repulsive Hubbard model in a bilayer is investigated using cluster dynamical mean field theory. For weak to intermediate values of Coulomb repulsion $U$, the system undergoes a transition from a Mott insulating phase to a metallic phase and then onto a band insulating phase as the interlayer hopping is increased. In the strong coupling case, the model exhibits a direct crossover from a Mott insulating phase to a band insulating phase. These results are robust with respect to the presence or absence of magnetic order.

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S. S. Kancharla, S. Okamoto. 2007-03-27. Band insulator to Mott insulator transition in a bilayer Hubbard model. https://doi.org/10.1103/physrevb.75.193103

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