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d-wave superconductivity and Pomeranchuk instability in the two-dimensional Hubbard model

Christoph J. Halboth·Walter Metzner
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Abstract

We present a systematic stability analysis for the two-dimensional Hubbard model, which is based on a new renormalization group method for interacting Fermi systems. The flow of effective interactions and susceptibilities confirms the expected existence of a d-wave pairing instability driven by antiferromagnetic spin fluctuations. More unexpectedly, we find that strong forward scattering interactions develop which may lead to a Pomeranchuk instability breaking the tetragonal symmetry of the Fermi surface.

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Christoph J. Halboth, Walter Metzner. 2000-03-21. d-wave superconductivity and Pomeranchuk instability in the two-dimensional Hubbard model. https://doi.org/10.1103/physrevlett.85.5162

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