Superconductivity in Pr-doped

Substitution of Pr at the Ca site in , with , has been reported. Pr is shown to substitute in the (BiPb)-2223 system, albeit with a simultaneous formation of Pr-doped (BiPb)-2212 phase in the samples. The x-ray analysis indicates that the latter phase grows continuously with increasing Pr concentration up to x = 0.4. For only Pr-doped (BiPb)-2212 phase is observed in the samples. The superconductor transition temperatures measured resistively shift to lower temperatures, with increasing Pr, at a rate of 5 K/(% Pr). The normal-state resistivity value and its temperature dependence are found to depend on the amount of Pr doping. We have further analysed the resistivity data of the pure and 5% (x = 0.1) doped samples for the fluctuation conductivity. Both samples exhibit 2D behaviour for the superconducting order parameter in the critical regime, within the Aslamazov-Larkin formulation.