Infield response of (Co)x/CuTl-1223 nanoparticles–superconductor composites

Abstract Infield superconducting properties of (Cu 0.5 Tl 0.5 )Ba 2 Ca 2 Cu 3 O 10− δ (CuTl-1223) superconducting phase after addition of cobalt (Co) nanoparticles were reported. Crystal structure of host CuTl-1223 phase was not affected after inclusion of Co nanoparticles. Superconducting resistive transition broadening was observed with applied magnetic field from 0 to 7 T, which was attributed to dissipation mechanism caused by thermally activated flux flow (TAFF) in the presence of small current (10 μA). Reduction in activation energy U o ( H ,  T ) showed suppression of flux pinning strength with increasing content of Co nanoparticles.