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Reflectivity measurements in uniaxial superconductors: a methodological discussion applied to the case of La(2-x)Sr(x)CuO(4)

M. Ortolani·P. Calvani·S. Lupi·P. Maselli·M. Fujita·K. Yamada
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Abstract

Most of the novel superconductors are uniaxial crystals, with metallic planes ($ab$) orthogonal to an insulating axis ($c$). Far-infrared measurements of the reflectivity $R_{ab} (ω)$ provide valuable information on their low-energy electrodynamics, but involve delicate experimental issues. Two of them are a possible contamination of $R_{ab} (ω)$ from the c axis and the extrapolation of the $R_{ab}$ data to $ω$ =0, both above and below $T_c$. Here we discuss quantitatively these issues with particular regard to La$_{2-x}$Sr$_x$CuO$_{4+y}$, one of the most studied high-$T_c$ materials.

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M. Ortolani, P. Calvani, S. Lupi, P. Maselli, M. Fujita, K. Yamada. 2004-07-16. Reflectivity measurements in uniaxial superconductors: a methodological discussion applied to the case of La(2-x)Sr(x)CuO(4). https://doi.org/10.1364/josab.22.001994

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