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Functional Renormalization Group calculation of the Fermi surface of a spin-ladder

Gilles Abramovici·Michel Héritier
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Abstract

We study non conventional superconductivity on a ladder, improving the predictions of the Hubbard model. The determination of the Fermi surface, in 2 or 3 dimensions, remains a very hard task, but it is exactly solvable for a single ladder. We use functional Renormalisation Group methods, which prove, here, scheme-dependant. In the superconducting phase, the binding/antibinding gap is stabilized, but in the antiferromagnetic phase, it shrinks and the ladder turns one-dimensional.

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Gilles Abramovici, Michel Héritier. 2007-02-19. Functional Renormalization Group calculation of the Fermi surface of a spin-ladder. https://doi.org/10.1103/physrevb.75.094516

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