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arXiv · 0802.0909

Magnetic and Transport Properties of a Coupled Hubbard Bilayer with Electron and Hole Doping

K. Bouadim·G. G. Batrouni·F. Hebert·R. T. Scalettar
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Abstract

The single band, two dimensional Hubbard Hamiltonian has been extensively studied as a model for high temperature superconductivity. While Quantum Monte Carlo simulations within the dynamic cluster approximation are now providing considerable evidence for a d-wave superconducting state at low temperature, such a transition remains well out of reach of finite lattice simulations because of the "sign problem". We show here that a bilayer Hubbard model, in which one layer is electron doped and one layer is hole doped, can be studied to lower temperatures and exhibits an interesting signal of d-wave pairing. The results of our simulations bear resemblance to a recent report on the magnetic and superconducting properties of Ba$_2$Ca$_3$Cu$_4$O$_8$F$_2$ which contains both electron and hole doped CuO$_2$ planes. We also explore the phase diagram of bilayer models in which each sheet is at half-filling.

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K. Bouadim, G. G. Batrouni, F. Hebert, R. T. Scalettar. 2008-02-07. Magnetic and Transport Properties of a Coupled Hubbard Bilayer with Electron and Hole Doping. https://doi.org/10.1103/physrevb.77.144527

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