The influence of nano-Cu addition on the superconductivity of YBCO

In present work, we have studied the effect of nano-crystalline Cu (nano-Cu) addition on properties of the bulk YBa2Cu3O7-delta superconductors. The results reveal that the T-c does not vary with the nano-Cu content. However, the intragranular critical density J(cm) improves due to nano-Cu addition, which gives evidence that the nano-Cu particles introduced into superconducting matrix take the role of effective flux pinning centers.