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Optical conductivity in the CuO double chains of PrBa_2Cu_4O_8: Consequences of charge fluctuation

R. Amasaki·Y. Shibata·Y. Ohta
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Abstract

We calculate the optical conductivity of the CuO double chains of PrBa$_2$Cu$_4$O$_8$ by the mean-field approximation for the coupled two-chain Hubbard model around quarter filling. We show that the $\sim$40 meV peak structure, spectral shape, and small Drude weight observed in experiment are reproduced well by the present calculation provided that the stripe-type charge ordering presents. We argue that the observed anomalous optical response may be due to the presence of stripe-type fluctuations of charge carriers in the CuO double chains; the fast time scale of the optical measurement should enable one to detect slowly fluctuating order parameters as virtually a long-range order.

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R. Amasaki, Y. Shibata, Y. Ohta. 2001-10-17. Optical conductivity in the CuO double chains of PrBa_2Cu_4O_8: Consequences of charge fluctuation. https://doi.org/10.1103/physrevb.66.012502

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