Effect of Pb Substitution on Superconducting and Normal State Electrical Properties of Bi2Sr2CaCu2O8+σ Nanopowders
Abstract.The powders of Bi2-xPbxSr2CaCu2O8+δ(x=0; 0.4) superconductor have been prepared by using dissolved method followed by short period of sintering and calcination process . The purpose of this research is to study about the Pb doped effect to the properties of BSCCO nanopowders especially in the electric and superconducting properties. Based on the previous result, BSCCO nanopowders have ferromagnetic properties at the room temperature. This characteristic is not appeared in bulk superconductor. The 2212 phase of Bi-based system has been formed and observed by using X-ray diffraction (XRD) measurement. The superconducting quantum interference device (SQUID) observation showed that the Bi2-xPbxSr2CaCu2O8+δ(x=0; 0.4) samples exhibited diamagnetic behaviour at the critical temperature, Tc=76 K and 78 K. The sample with partial Pb substitution exhibited stronger permanency to the external magnetic field indicating presence of flux pinning. The four point probe (FPP) measurement showed that the sample partially doped with Pb has lower resistivity (more metallic) than the Pb-free sample in the normal state.