Optical properties of overdoped YBa2Cu3Ox || C : evidence for superconductivity in the chains
Institut für angewandte Physik, Universität Karlsruhe D-76128
2 Forschungszentrum Karlsruhe, Institut für Technische Physik D-76021 Karlsruhe, Germany
Accepted: 1 December 1995
We report on temperature-dependent reflectance measurements on several single crystals with in the far-infrared range (5 meV meV) with . Performing a Kramers-Kronig transformation, we derive the optical conductivity and the real part of the dielectric constant . Fitting the data with a two-fluid model, we obtained the superfluid carrier density and the scattering rate. The crystals of oxygen content x< 6.93, i.e., below the maximum value of Tc, show a linear dependence of the superfluid carrier density with temperature, consistent with the wave model. The data for the overdoped crystals give evidence for superconductivity of the chain carriers.
PACS: 74.25.Nf – Response to electromagnetic fields (nuclear magnetic resonance, surface impedance, etc.) / 74.72.Bk – Y-based compounds / 78.30.-j – Infrared and Raman spectra and scattering
© EDP Sciences, 1996