In–Plane and Out–of–Plane Optical Properties of NdBa2Cu3Ox Single Crystals Close to x = 7.0

AbstractWe present results of reflectivity measurements withE∥candE ⊥ con NdBa2Cu3Ox(Nd123) single crystals close to full oxygen doping. Along the c–axis the optical conductivity $$\sigma _1^c $$ shows a well developed absorption band around 450 cm−1at all temperatures. The in–plane optical properties are dominated by crystal–field excitations at low energies, a prominent step at 400 cm−1and a weaker feature between 500 - 550 cm−1. A comparison of $$\sigma _1^c $$ and the in–plane scattering rate Γab(ω) 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.