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Intersite Fluctuations and Spin-Charge Separation in the Extended Hubbard Model

J. Lleweilun Smith·Qimiao Si
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Abstract

We study the effects of intersite RKKY-like interactions in the mixed valence regime of a two-band extended Hubbard model. This model is known to display a metallic non-Fermi liquid state with spin-charge separation in the standard $D=\infty$ limit (where interactions lead to purely on-site fluctuations only). Using an extended $D=\infty$ approach, we find that the spin-charge separation survives the quantum fluctuations associated with arbitrary intersite density-density interactions and a finite range of intersite spin-exchange interactions. We determine the qualitative behavior of the spin, charge, and single-particle correlation functions. The implications of these results for the solution in finite spatial dimensions are discussed.

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J. Lleweilun Smith, Qimiao Si. 1997-05-14. Intersite Fluctuations and Spin-Charge Separation in the Extended Hubbard Model. https://arxiv.org/abs/cond-mat/9705140

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