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arXiv · 0708.2313

Comparative study of electron and hole doped High-Tc compounds in pseudogap regime: LDA+DMFT+Sk approach

I. A. Nekrasov·E. E. Kokorina·E. Z. Kuchinskii·Z. V. Pchelkina·M. V. Sadovskii
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Abstract

Pseudogap regime for the prototype high-Tc compounds hole doped Bi2Sr2CaCu2O8-x (Bi2212) and electron doped Nd2-xCexCuO4 (NCCO) is described by means of novel generalized LDA+DMFT+Sk approach. Here conventional dynamical mean-field theory (DMFT) equations are supplied with additional (momentum dependent) self-energy Sk. In the present case Sk describes non-local dynamical correlations induced by short-ranged collective Heisenberg-like antiferromagnetic spin fluctuations. Material specific model parameters of two neighboring CuO2 layers of Bi2212 and single CuO2 layer of NCCO were obtained within local density approximation (LDA) and constrained LDA method. We show that Fermi surface in presence of the pseudogap fluctuations have perfectly visible "hot-spots" for NCCO while in Bi2212 there is just rather broad region with strong antiferromagnetic scattering. Results obtained are in good agreement with recent ARPES and optical experiments.

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I. A. Nekrasov, E. E. Kokorina, E. Z. Kuchinskii, Z. V. Pchelkina, M. V. Sadovskii. 2007-09-03. Comparative study of electron and hole doped High-Tc compounds in pseudogap regime: LDA+DMFT+Sk approach. https://doi.org/10.1016/j.jpcs.2008.06.120

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