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Kinematics of electrons near a Van Hove singularity

J. Gonzalez·F. Guinea·M. A. H. Vozmediano
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Abstract

A two dimensional electronic system, where the Fermi surface is close to a Van Hove singularity, shows a variety of weak coupling instabilities, and it is a convenient model to study the interplay between antiferromagnetism and anisotropic superconductivity. We present a detailed analysis of the kinematics of the electron scattering in this model. The similitudes, and differences, between a standard Renormalization Group approach and previous work based on parquet summations of log$^2$ divergences are analyzed, with emphasis on the underlying physical processes. General properties of the phase diagram are discussed.

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J. Gonzalez, F. Guinea, M. A. H. Vozmediano. 1999-05-12. Kinematics of electrons near a Van Hove singularity. https://doi.org/10.1103/physrevlett.84.4930

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