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arXiv · 1411.3541

Superfluidity and Density Order in a Bilayer Extended Hubbard Model

Tuomas I. Vanhala·Jildou E. Baarsma·Miikka O. J. Heikkinen·Matthias Troyer·Ari Harju·Päivi Törmä
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Abstract

We use cluster dynamical mean field theory to study the phase diagram of the square lattice bilayer Hubbard model with an interlayer interaction. The layers are populated by two-component fermions, and the densities in both layers and the strength of the interactions are varied. We find that an attractive interlayer interaction can induce a checkerboard density ordered phase and superfluid phases, with either interlayer or intralayer pairing. Remarkably, the latter phase does not require an intralayer interaction to be present: it can be attributed to an induced attractive interaction caused by density fluctuations in the other layer.

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Tuomas I. Vanhala, Jildou E. Baarsma, Miikka O. J. Heikkinen, Matthias Troyer, Ari Harju, Päivi Törmä. 2016-04-20. Superfluidity and Density Order in a Bilayer Extended Hubbard Model. https://doi.org/10.1103/physrevb.91.144510

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