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Quasiparticles and c-axis coherent hopping in high T_c superconductors

P. S. Cornaglia·K. Hallberg·C. A. Balseiro
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Abstract

We study the problem of the low-energy quasiparticle spectrum of the extended t-J model and analyze the coherent hopping between weakly coupled planes described by this model. Starting with a two-band model describing the Cu-O planes and the unoccupied bands associated to the metallic atoms located in between the planes, we obtain effective hopping matrix elements describing the c-axis charge transfer. A computational study of these processes shows an anomalously large charge anisotropy for doping concentrations around and below the optimal doping.

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P. S. Cornaglia, K. Hallberg, C. A. Balseiro. 2001-12-20. Quasiparticles and c-axis coherent hopping in high T_c superconductors. https://doi.org/10.1103/physrevb.63.060504

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