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In-Plane and Out-of-Plane Optical Properties of NdBa2Cu3Ox Single Crystals close to x = 7.0

R. Hauff·M. Goeppert·B. Obst·Th. Wolf·P. Schweiss·H. Wuehl
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Abstract

We present results of reflectivity measurements with E parallel to c and E perpendicular to c on NdBa2Cu3Ox (Nd123) single crystals close to full oxygen doping. Along the c-axis the optical conductivity shows a well developed absorption band around 450 cm^-1 at all temperatures. The in-plane optical properties are dominated by crystal-field excitations at low energies, a prominent step at 400 cm^-1 and a weaker feature between 500 - 550 cm^-1. A comparison of the c-axis optical conductivity and the in-plane scattering rate with neutron scattering derived spin susceptibility spectra suggests that the in-plane and out-of-plane anomalies are caused by the same mechanism, probably electron--spin scattering.

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R. Hauff, M. Goeppert, B. Obst, Th. Wolf, P. Schweiss, H. Wuehl. 1999-12-17. In-Plane and Out-of-Plane Optical Properties of NdBa2Cu3Ox Single Crystals close to x = 7.0. https://arxiv.org/abs/cond-mat/9912333

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