Thermal Conductivity and Thermoelectric Power of Yb-Substituted Bi-2212 Superconductor

Abant Izzet Baysal University;Bulent Ecevit University;Cukurova University;Gazi University;Inonu University9th International Conference on Magnetic and Superconducting Materials, MSM 2015 --30 April 2015 through 3 May 2015 -- --In the present study, Bi2Sr2CaCu2-xYbxO8+y where x = 0.0, 0.05, 0.1 and 0.25, superconductor materials were textured using the Laser Floating Zone technique. After annealing the as-grown materials, they were characterized by thermal conductivity (?-T), thermoelectric power (S-T), and electrical resistivity (R-T) measurements performed from room temperature down to 20 K. The thermoelectric power is positive in all cases and is found to increase with decreasing temperature, reaching the maximum value (peak) around the samples TC values and dropping rapidly to zero below TC. Electrical resistivity measurements show a slight decrease of TC when Yb substitution is raised. In spite of this effect, TC values are higher than 90 K in all cases. On the other hand, Yb substitution also decreases thermal conductivity, compared with the undoped samples