Magnetoresistivity studies for BiPb-2223 phase added by BaSnO₃ nanoparticles

Co-precipitation method and conventional solid-state reaction technique were used to synthesize BaSnO₃ nanoparticles and (BaSnO₃)_x/Bi_1.6Pb_0.4Sr₂Ca₂Cu₃O_10+δ (0 ≤ x ≤ 1.50 wt%) samples, respectively. X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and electrical resistivity data were used to characterize BiPb-2223 phase added by BaSnO₃ nanoparticles. The relative volume fraction and superconducting transition temperature T_c of BiPb-2223 phase were enhanced by increasing BaSnO₃ addition up to 0.50 wt%. These parameters were decreased with further increase of x. The resistive transition broadening under different applied DC magnetic fields (0.29-4.40 kG) was analyzed through thermally activated flux creep (TAFC) model and Ambegaokar-Halperin (AH) theory. Improvements of the derived flux pinning energy U, critical current density J_c (0) estimated from AH parameter C(B), and upper critical magnetic field $B_{\text{c2}}\text{(0)}$, were recorded by adding BaSnO₃ nanoparticles up to 0.50 wt%, beyond which these parameters were suppressed. The magnetic field dependence of the flux pinning energy and critical current density decreased as a power-law relation, which indicated the single junction sensitivity between the superconducting grains to the applied magnetic field. Furthermore, the increase in the applied magnetic field did not affect the electronic thermal conductivity ${\kappa }_{\text{e}}$ above the superconducting transition temperature and suppressed it below T_c .