Effect of (Ta/Nb) co-doping on the magnetoresistivity and flux pinning energy of the BPSCCO superconductors

ÖZÇELİK B., Gundogmus H., Yazici D.

JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS, cilt.25, sa.6, ss.2456-2462, 2014 (SCI-Expanded) identifier identifier

Özet

In the present work, the effect of co-doping of Ta and Nb with nominal composition of (BiPb)(2)TaxSr2Ca3Cu4-yNbyO12+delta where x = 0.1 and y = 0.0, 0.025, 0.05, 0.075, and 0.1 were investigated. The samples were prepared by using the well-known conventional standard solid-state reaction method. The magnetoresistance measurements were studied for different values of the applied magnetic field. The activation energies, irreversibility fields (H (irr) ), upper critical fields (H (c2) ) and coherence lengths at 0 K (zeta(0)) were calculated from the resistivity versus temperature (rho-T) curves, under DC magnetic fields up to 6 T. The thermally activated flux flow (TAFF) model has been applied in order to calculate the flux pinning energies. The results have shown that the upper critical magnetic field, H (c2) (0), and the flux pinning energies vary from similar to 113 to 74 T and similar to 384 to 101 meV at 0 T, with the Nb-content, respectively.

In the present work, the effect of co-doping of Ta and Nb with nominal composition of (BiPb)(2)TaxSr2Ca3Cu4-yNbyO12+delta where x = 0.1 and y = 0.0, 0.025, 0.05, 0.075, and 0.1 were investigated. The samples were prepared by using the well-known conventional standard solid-state reaction method. The magnetoresistance measurements were studied for different values of the applied magnetic field. The activation energies, irreversibility fields (H (irr) ), upper critical fields (H (c2) ) and coherence lengths at 0 K (zeta(0)) were calculated from the resistivity versus temperature (rho-T) curves, under DC magnetic fields up to 6 T. The thermally activated flux flow (TAFF) model has been applied in order to calculate the flux pinning energies. The results have shown that the upper critical magnetic field, H (c2) (0), and the flux pinning energies vary from similar to 113 to 74 T and similar to 384 to 101 meV at 0 T, with the Nb-content, respectively.