Superconductivity and magnetism in Ru1−xIrxSr2GdCu2O8 compounds

• Published in: Physica. C, Superconductivity Vol. 408-410; pp. 195 - 196
• Main Authors: Torikachvili, M.S., Bossi, I., O'Brien, J.R., Fonseca, F.C., Muccillo, R., Jardim, R.F.
• Format: Journal Article
• Language: English
• Published: 01.08.2004
• ISSN: 0921-4534
• DOI: 10.1016/j.physc.2004.02.086

We carried out an investigation of the magnetic and superconducting properties of Ru1-xIrxSr2GdCu2O8 compounds for Ir concentrations up to x=0.25, which is the limit of solubility. This study consisted in the X-ray diffraction analysis of these materials, and the measurements of the temperature dependence of the electrical resistivity, and of the ac and dc magnetic susceptibilities. The substitution of Ir for Ru moves the magnetic transition of the Ru-sublattice near 130 K to lower temperatures, and it suppresses superconductivity fairly rapidly. The zero-resistance state drops from 32 K for the pure Ru-1212 compound to 13 K for x=0.10. Further addition of Ir causes a gradual evolution from metallic to non-metallic behavior, with progressively larger upturns at low temperatures.