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Electronic spectrum in high-temperature cuprate superconductors

N. M. Plakida·V. S. Oudovenko
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Abstract

A microscopic theory for electronic spectrum of the CuO2 plane within an effective p-d Hubbard model is proposed. Dyson equation for the single-electron Green function in terms of the Hubbard operators is derived which is solved self-consistently for the self-energy evaluated in the noncrossing approximation. Electron scattering on spin fluctuations induced by kinematic interaction is described by a dynamical spin susceptibility with a continuous spectrum. Doping and temperature dependence of electron dispersions, spectral functions, the Fermi surface and the coupling constant are studied in the hole doped case. At low doping, an arc-type Fermi surface and a pseudogap in the spectral function are observed.

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N. M. Plakida, V. S. Oudovenko. 2006-10-05. Electronic spectrum in high-temperature cuprate superconductors. https://doi.org/10.1134/s1063776107020082

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