Quasiparticle bands and superconductivity in bilayer cuprates.

Liechtenstein A.I., Gunnarsson O., Andersen O.K., Martin R.M.

We analyze the generic features of the energy spectrum for two coupled CuO2 layers with a realistic extended Hubbard model. The quasiparticle bands exhibit flat regions near X(Y) points in the Brillouin zone with a large reduction of the bonding-antibonding splitting and pinning of extended van Hove singularity to the Fermi level, which is more efficient for bilayers than for a single layer. In contrast to the results with simpler models, the superconducting temperature for d(x2-y2) pairing is not lowered by the bilayer hopping.

Physical Review B, 54 12505-8, 1996.

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