Effect of FePd nanoparticle addition on the superconductivity of Bi 1 . 6 Pb 0 . 4 Sr 2 Ca 2 Cu 3 O 10+δ compounds

We investigated the effect of Fe 50 Pd 50 nanoparticle addition on the crystal structure and superconductivity of Bi 1. 6 Pb 0. 4 Sr 2 Ca 2 Cu 3 O 10+δ compounds. Pure and Fe 50 Pd 50 -added Bi 1. 6 Pb 0. 4 Sr 2 Ca 2 Cu 3 O 10+δ samples with different additional contents were prepared by the solid-state reaction technique. Crystal structure and surface morphology of the fabricated samples revealed the formation of Bi-2223 and Bi-2212 superconducting phases. The critical temperature ( T c ) of the Fe 50 Pd 50 -added samples was lower than that of the pure one. In comparison with the pure sample, magnetization J c was clearly enhanced for the samples with the addition of Fe 50 Pd 50 having stronger magnetic properties. The enhancement in J c was possibly explained by the fact that Fe 50 Pd 50 nanoparticles served as effective pinning centers. Dominant pinning mechanisms of all samples were analyzed to be δl pinning by the collective pinning theory. The geometry of artificial pinning centers was identified to be normal core volume and point-like pinning by using the Dew–Hughes model.