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Anomalous behaviors of the charge and spin degrees of freedom in the CuO double chains of PrBa$_2$Cu$_4$O$_8$

Satoshi Nishimoto·Yukinori Ohta
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Abstract

The density-matrix renormalization-group method is used to study the electronic states of a two-chain Hubbard model for CuO double chains of PrBa$_2$Cu$_4$O$_8$. We show that the model at quarter filling has the charge ordered phases with stripe-type and in-line--type patterns in the parameter space, and in-between, there appears a wide region of vanishing charge gap; the latter phase is characteristic of either Tomonaga-Luttinger liquid or a metallic state with a spin gap. We argue that the low-energy electronic state of the CuO double chains of PrBa$_2$Cu$_4$O$_8$ should be in the metallic state with a possibly small spin gap.

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Satoshi Nishimoto, Yukinori Ohta. 2003-05-26. Anomalous behaviors of the charge and spin degrees of freedom in the CuO double chains of PrBa$_2$Cu$_4$O$_8$. https://doi.org/10.1103/physrevb.68.235114

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