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Frustration of antiferromagnetism in the t-t'-Hubbard model at weak coupling

W. Hofstetter·D. Vollhardt
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Abstract

The perfect-nesting instability towards antiferromagnetism of the Hubbard model is suppressed by next-nearest neighbor hopping t'. The exact asymptotic behavior of the critical coupling U_c(t') at small t' is calculated in dimensions d=2,3 and infinity using Hartree theory, and the order of the transition is determined. A region of stability of a metallic antiferromagnetic phase in d=3 is identified.

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W. Hofstetter, D. Vollhardt. 1998-04-14. Frustration of antiferromagnetism in the t-t'-Hubbard model at weak coupling. https://doi.org/10.1002/andp.2060070105

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