The effects of doping on the structural and physical properties in the BSCCO superconductors

ABSTRACTPhD THESISTHE EFFECTS OF DOPING ON THE STRUCTURAL AND PHYSICALPROPERTIES IN THE BSCCO SUPERCONDUCTORSAhmet EKİCİBİLDEPARTMENT OF PHYSICSINSTITUTE OF NATURAL AND APPLIED SCIENCESUNIVERSITY OF CUKUROVASupervisor : Prof.Dr.Bekir ÖZÇELİKYear: 2005, Pages: 147Jury: Prof.Dr.Bekir ÖZÇELİKProf.Dr.Kerim KIYMAÇProf.Dr. Emirullah MEHMETOVProf.Dr. Osman SERİNDAĞAssoc.Prof.H.İbrahim ADIGÜZELThe purpose of this work is to investigate the structural, electrical andmagnetic properties of Sm and Gd doped of BSCCO superconductor systemfabricated by using the conventional glass-ceramic method. For this reason, in firstpart of this work; the microstructural and physical properties of high temperaturesuperconductos, BSSCCO have been summarized. In order to explain the origin ofthe magnetic properties some theories proposed are reviewed. In other part of thisthesis, the magnetic, physical, structural properties and phase transition of theBSCCO superconductors have been surveyed. Microstructural, physical andsuperconducting changes occured during the heat treatments have been analysed byusing Differantial Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), ScanningElectron Microscopy (SEM), and Resistivity Measurements (R-T). The Closed CycleVSM (Vibrating Sample Magnetometer) has been used for the magneticmeasurements, like M-H, dM/dH, hysteresis loops, Hc, Jc and Mr. The resultsindicated that the superconducting properties of samples were slightly degradedwhen Sm and Gd were added into BSCCO system. Finally, the results of the Sm andGd doped samples comparedKey Words: BSCCO, XRD, SEM, Dynamics Susceptibilities, Critical CurrentDensityII