JOURNAL OF LOW TEMPERATURE PHYSICS, vol.174, pp.136-147, 2014 (SCI-Expanded)
In this study, the effect of Ce doping on the properties of Bi2Sr2Ca1-x Ce (x) Cu2O8+delta ceramic superconductors, with x=0.0, 0.01, 0.05, 0.1, and 0.25, has been investigated. Samples' precursors were prepared using the conventional solid state method and subsequently textured using the Laser Floating Zone technique. The magnetoresistance measurements were studied under various applied magnetic fields. The activation energies, irreversibility fields (H (irr) ), upper critical fields (H (c2)) and coherence lengths at 0 K (xi(0)) were calculated from the resistivity versus temperature (rho-T) curves, under DC magnetic fields up to 5 T. The thermally activated flux flow model has been applied in order to calculate the flux pinning energies. The results indicated that H (c2)(0) varied from 416.19 to 115 T and the flux pinning energies varied from 1.46 to 0.042 eV at 0 T.