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Anisotropic Fermi surfaces and Kohn-Luttinger superconductivity in two dimensions

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

The instabilities induced on a two-dimensional system of correlated electrons by the anisotropies of its Fermi line are analyzed on general grounds. Simple scaling arguments allow to predict the opening of a superconducting gap with a well-defined symmetry prescribed by the geometry of the Fermi line. The same arguments predict a critical dimension of 3/2 for the transition of the two-dimensional system to non-Fermi liquid behavior. The methods are applied to the t-t' Hubbard model in a wide range of dopings.

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J. Gonzalez, F. Guinea, M. A. H. Vozmediano. 2000-01-27. Anisotropic Fermi surfaces and Kohn-Luttinger superconductivity in two dimensions. https://doi.org/10.1142/s0217979299002526

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