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Re-integerization of fractional charges in the correlated quarter-filled band

R. T. Clay·S. Mazumdar·D. K. Campbell
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Abstract

Previous work has demonstrated the existence of soliton defect states with charges +/- e/2 in the limits of zero and of infinite on-site Coulomb interactions in the one-dimensional (1D) quarter-filled band. For large but finite on-site Coulomb interaction, the low temperature 2k_F bond distortion that occurs within the 4k_F bond-distorted phase is accompanied by charge-ordering on the sites. We show that a ``re-integerization'' of the defect charge occurs in this bond-charge density wave (BCDW) state due to a ``binding'' of the fractional charges. We indicate briefly possible implications of this result for mechanisms of organic superconductivity.

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R. T. Clay, S. Mazumdar, D. K. Campbell. 2000-10-18. Re-integerization of fractional charges in the correlated quarter-filled band. https://doi.org/10.1103/physrevlett.86.4084

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