Enhancement in the high-T-c phase of BSCCO superconductors by Nb addition

Sozeri, Huseyin
Ghazanfari, Nader
Ozkan, Husnu
Kilic, Ahmet
Pure and Nb2O5 added Bi1.6Pb0.4Nbx Sr2Ca2Cu3O delta superconductors ( x varies up to 0.30) were synthesized by the solid state reaction method. Structural and superconducting properties of the samples were investigated. The fraction of the high-T-c phase ( 2223) increases with Nb addition up to x = 0.10, for which a nearly single 2223 phase was obtained. The critical temperature of the samples increases from 96 to 104 K with doping up to x = 0.20 and a further increase in Nb decreases the Tc sharply. Similarly, there is a considerable enhancement in the critical current density ( jc) of the samples in the same doping range. Both AC susceptibility and transport measurements showed that the optimum Nb concentration is x = 0.20. The out- of- phase component of the AC susceptibility measurements showed that inter- grain coupling was enhanced up to the same doping level. Nb additions above x = 0.30 decrease the fraction of the high- Tc phase and degrade the superconducting properties. Present measurements indicate that x = 0.20 is the optimum Nb concentration in the BSCCO superconductor to enhance phase purity, inter- grain coupling and superconducting parameters ( Tc and j(c)).


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Kayed, TS; Ozkan, H; Hasanlı, Nızamı; Ercan, I (IOP Publishing, 2000-12-01)
The critical temperature and critical current of Bi-2223 tapes have been studied near T-c under a magnetic field and gamma -irradiation. T-c decreases from 109 to 96 K with an increase in B up to 100 mT. In the 100-110 K range I-c decreases by about 75-85% at steady rates in low fields up to 20-50 mT, then decreases to zero at slower rates with further increase of field. The I-c versus B plots are non-exponential in small fields (up to 30 mT at 100 K and up to 10 mT at 108 K) and change to exponential form ...
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Kayed, TS; Ozkan, H; Hasanlı, Nızamı (IOP Publishing, 2001-09-01)
The effects of lithium doping on the formation and properties of the T1-based superconductors have been studied. Lithium atoms up to around 3 mol.% have been added to the oxides of nominal composition Tl1.8Ba2Ca2.2Cu3Ox, and the usual solid-state reaction method has been applied. Lithium additions in the range 0.23-0.29 mol.% increase the fraction of the Tl-2223 phase and significantly improve the critical temperature of the samples. Higher amounts of lithium additions diminish the Tl-2223 phase, reduce the...
Evolution of magnetic and structural properties of TiO2 with Co-doping
Topal, Ugur; Ozkan, Husnu; Bakan, Halil I.; Cankur, Oktay; Topal, Kevser (Elsevier BV, 2008-03-15)
This paper presents the phase formations and magnetic properties of Co-doped TiO2 synthesized by the colloidal and ammonium nitrate melt techniques (ANMT). The phase formations and ferromagnetic properties were studied with XRD and SQUID magnetometry. Crystallization of the TiO2 rutile lattice was completed at 1000 degrees C and that was preserved during annealing up to 1300 degrees C. For the samples annealed at 1200 degrees C, elemental analysis has shown that the colloidal technique leads to a single-pha...
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Ertas, M; Çırpan, Ali; Toppare, Levent Kamil (Elsevier BV, 2004-05-07)
A new dipyrrolyl monomer was synthesized via the reaction between 4-pyrrol-1-yl phenol and butanedioyl dichloride. Electrochemical behavior of this monomer, succinic acid bis-(4-pyrrol-1-yl-phenyl) ester (SM) was studied. Homopolymerization was achieved by chemical and constant Current electrolysis methods. Copolymerization of SM with thiophene was performed by constant potential electrolysis in acetonitrile (AN)-tetrabutylammonium tetrafluoroborate (TBAFB) and dichloromethane (DCM)-TBAFB, solvent-electroly...
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In this study, high T-c superconducting thin films of Y-Ba-Cu-O system have been prepared onto single crystals of LaAlO3 (100) and SrTiO3 (100) by resistive evaporation of YF3, BaF2 and Cu powders and a subsequent multi-stage annealing. In the deposition process, two different methods were used: mixed-powder method and sequential-deposition method. The best quality films were achieved on LaAlO3 substrates by using sequential-deposition technique with offset critical transition temperature of 88.1 K. Charact...
Citation Formats
H. Sozeri, N. Ghazanfari, H. Ozkan, and A. Kilic, “Enhancement in the high-T-c phase of BSCCO superconductors by Nb addition,” SUPERCONDUCTOR SCIENCE & TECHNOLOGY, pp. 522–528, 2007, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/67653.