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arXiv · 1203.2887

Incommensurate nematic fluctuations in the two-dimensional Hubbard model

Christoph Husemann·Walter Metzner
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Abstract

We analyze effective d-wave interactions in the two-dimensional extended Hubbard model at weak coupling and small to moderate doping. The interactions are computed from a renormalization group flow. Attractive d-wave interactions are generated via antiferromagnetic spin fluctuations in the pairing and charge channels. Above Van Hove filling, the d-wave charge interaction is maximal at incommensurate diagonal wave vectors, corresponding to nematic fluctuations with a diagonal modulation. Below Van Hove filling a modulation along the crystal axes can be favored. The nematic fluctuations are enhanced by the nearest-neighbor interaction in the extended Hubbard model, but they always remain smaller than the dominant antiferromagnetic, pairing, or charge density wave fluctuations.

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Christoph Husemann, Walter Metzner. 2012-03-13. Incommensurate nematic fluctuations in the two-dimensional Hubbard model. https://doi.org/10.1103/physrevb.86.085113

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