Models of the Pseudogap State of Two-Dimensional Systems

E. Z. Kuchinskii; M. V. Sadovskii

doi:10.1134/1.558879

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Models of the Pseudogap State of Two-Dimensional Systems

E. Z. Kuchinskii·M. V. Sadovskii

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Abstract

We analyze a number of ``nearly exactly'' solvable models of electronic spectrum of two-dimensional systems with well-developed fluctuations of short range order of ``dielectric'' (e.g. antiferromagnetic) or ``superconducting'' type, which lead to the formation of anisotropic pseudogap state on certain parts of the Fermi surface. We formulate a recurrence procedure to calculate one-electron Green's function which takes into account all Feynman diagrams in perturbation series and is based upon the approximate Ansatz for higher-order terms in this series. Detailed results for spectral densities and density of states are presented. We also discuss some important points concerning the justification of our Ansatz for higher-order contributions.

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E. Z. Kuchinskii, M. V. Sadovskii. 1998-08-29. Models of the Pseudogap State of Two-Dimensional Systems. https://doi.org/10.1134/1.558879

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