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Far-infrared c-axis conductivity of flux-grown Y$_{1-x}$Pr$_{x}$Ba$_{2}$Cu$_{3}$O$_{7}$ single crystals studied by spectral ellipsometry

C. Bernhard·T. Holden·A. Golnik·C. T. Lin·M. Cardona
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Abstract

The far-infrared c-axis conductivity of flux-grown Y$_{1-x}$Pr$_{x}$Ba$_{2}$Cu$_{3}$O$_{7}$ single crystals with 0.2$\leq $x$\leq $0.5 has been studied by sepectral ellipsometry. We find that the c-axis response exhibits spectral features similar to deoxygenated underdoped YBa$_{2}$Cu$_{3}$O$_{7-δ}$, i.e., a pseudogap develops in the normal state, the phonon mode at 320 cm$^{-1}$ exhibits an anomalous T-dependence and an additional absorption peak forms at T. This suggests that the T$_{c}$ suppression in flux grown Pr-substituted crystals is caused by a decrease of the hole content and/or by carrier localization rather than by pair breaking.

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C. Bernhard, T. Holden, A. Golnik, C. T. Lin, M. Cardona. 2000-05-11. Far-infrared c-axis conductivity of flux-grown Y$_{1-x}$Pr$_{x}$Ba$_{2}$Cu$_{3}$O$_{7}$ single crystals studied by spectral ellipsometry. https://doi.org/10.1103/physrevb.62.9138

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