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On the correllation effect in Peierls-Hubbard chains

J. Malek·S. -L. Drechsler·S. Flach·E. Jeckelmann·K. Kladko
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Abstract

We reexamine the dimerization, the charge and the spin gaps of a half-filled Peierls-Hubbard chain by means of the incremental expansion technique. Our numerical findings are in significant quantitative conflict with recently obtained results by M. Sugiura and Y. Suzumura [J. Phys. Soc. Jpn. v. 71 (2002) 697] based on a bosonization and a renormalization group method, especially with respect to the charge gap. Their approach seems to be valid only in the weakly correlated case.

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J. Malek, S. -L. Drechsler, S. Flach, E. Jeckelmann, K. Kladko. 2002-10-16. On the correllation effect in Peierls-Hubbard chains. https://doi.org/10.1143/jpsj.72.2277

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