The Effect of Both Temperature and Magnetic Field on Magnetic Hysteresis of (Cu0.25Tl0.75)Ba2Ca3Cu4O12-δ Superconductor Added with Nano-(Zn0.95Ni0.05O)

The effects of both magnetic field and temperature on the magnetic hysteresis of (Zn0.95Ni0.05O)x/(Cu0.25Tl0.75)Ba2Ca3Cu4O12 − δ, x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0 wt.%, were studied. The magnetic parameters such as the lower “Hc1” and the upper “Hc2” critical magnetic fields, the zero temperature coherence length [ξ(0], the coercive field Hcoer., the remanent magnetization Mr, the vertical width Δ M, the magnetic critical current density Jc.mag, and the flux pinning density Fp were extracted from the analysis of the hysteresis loops. The experimental data of the Jc.mag were analyzed according to the power law, Kim model, and the exponential model. The results showed that the exponential model is more convenient in describing the obtained data than the power law and Kim models. In addition, with increasing the applied magnetic field, the samples containing nano-Zn0.95Ni0.05O were degraded less compared with the pure sample (Cu0.25Tl0.75)-1234. Thus, nano-Zn0.95Ni0.05O-addition to (Cu, Tl)-1234 had a significant effect on improving Jc.mag values.