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arXiv · 0903.3168

Incommensurate antiferromagnetic fluctuations in the two-dimensional Hubbard model

H. C. Krahl·S. Friederich·C. Wetterich
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Abstract

Commensurate and incommensurate antiferromagnetic fluctuations in the two-dimensional repulsive t-t'-Hubbard model are investigated using functional renormalization group equations. For a sufficient deviation from half filling we establish the existence of local incommensurate order below a pseudocritical temperature T_{pc}. Fluctuations not accounted for in the mean field approximation are important--they lower T_{pc} by a factor \approx2.5.

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H. C. Krahl, S. Friederich, C. Wetterich. 2009-03-18. Incommensurate antiferromagnetic fluctuations in the two-dimensional Hubbard model. https://doi.org/10.1103/physrevb.80.014436

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