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arXiv · 0911.4028

Correlation function for the one-dimensional extended Hubbard model at quarter filling

S. Nishimoto·M. Tsuchiizu
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Abstract

We examine the density-density correlation function in the Tomonaga-Luttinger liquid state for the one-dimensional extended Hubbard model with the on-site Coulomb repulsion $U$ and the intersite repulsion $V$ at quarter filling. By taking into account the effect of the marginally irrelevant umklapp scattering operator by utilizing the renormalization-group technique based on the bosonization method, we obtain the generalized analytical form of the correlation function. We show that, in the proximity to the gapped charge-ordered phase, the correlation function exhibits anomalous crossover between the pure power-law behavior and the power-law behavior with logarithmic corrections, depending on the length scale. Such a crossover is also confirmed by the highly-accurate numerical density-matrix renormalization group method.

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S. Nishimoto, M. Tsuchiizu. 2009-11-20. Correlation function for the one-dimensional extended Hubbard model at quarter filling. https://doi.org/10.1103/physrevb.81.085116

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