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In-Plane Spectral Weight Shift of Charge Carriers in $YBa_2Cu_3O_{6.9}$

A. V. Boris·N. N. Kovaleva·O. V. Dolgov·T. Holden·C. T. Lin·B. Keimer·C. Bernhard
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Abstract

The temperature dependent redistribution of the spectral weight of the $CuO_2$ plane derived conduction band of the $YBa_2Cu_3O_{6.9}$ high temperature superconductor (T_c = 92.7 K) was studied with wide-band (from 0.01 to 5.6 eV) spectroscopic ellipsometry. A superconductivity - induced transfer of the spectral weight involving a high energy scale in excess of 1 eV was observed. Correspondingly, the charge carrier spectral weight was shown to decrease in the superconducting state. The ellipsometric data also provide detailed information about the evolution of the optical self-energy in the normal and superconducting states.

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A. V. Boris, N. N. Kovaleva, O. V. Dolgov, T. Holden, C. T. Lin, B. Keimer, C. Bernhard. 2004-05-04. In-Plane Spectral Weight Shift of Charge Carriers in $YBa_2Cu_3O_{6.9}$. https://doi.org/10.1126/science.1095532

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