اثر نانو ذرات نقره به عنوان مراکز میخکوبی شار در ابررسانای YBa2cu3o7-δ

  The objective of this work is to investigate the effect of Ag nanoparticles as the flux pinning centers. Ag nanoparticles with different particle sizes from 30 to 1000 nm were prepared through the chemical reduction of AgNO3 in an alcohol solution. Then, samples of YBa2Cu3O7-δ superconductors were doped by 1 and 2 weight percentage of Ag nanoparticles with different sizes. Samples were characterized by XRD, SEM and EDX measurements. Critical current measurement was performed using a standard four probe technique at liquid nitrogen temperature. The results show by increasing of Ag nanoparticle sizes up to 700 nm, the Jc increases, but decreases by further increase in Ag particle size. Also, we found that the samples with 2 weigh percentage of Ag nanoparticles show more increase in Jc .