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On the violation of the Fermi-liquid picture in two-dimensional systems owing to the Van-Hove singularities

V. Yu. Irkhin·A. A. Katanin
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Abstract

We consider the two-dimensional t-t' Hubbard model with the Fermi level being close to the van Hove singularities. The phase diagram of the model is discussed. In a broad energy region the self-energy at the singularity points has a nearly-linear energy dependence. The corresponding correction to the density of states is proportional to ln^3(e). Both real- and imaginary part of the self-energy increase near the quantum phase transition into magnetically ordered or superconducting phase which implies violation of the Fermi-liquid behavior. The application of the results to cuprates is discussed.

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V. Yu. Irkhin, A. A. Katanin. 2002-05-06. On the violation of the Fermi-liquid picture in two-dimensional systems owing to the Van-Hove singularities. https://doi.org/10.1103/physrevb.64.205105

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