Enhancement of critical current property of YBCO superconductor doped with nano sized Gd

It is seen that with the incorporation of nano dopants, there is a considerable increase in the current carrying capacity of the superconducting material YBCO. In this paper, we report preparation of YBa₂Cu₃O_7-x using solid state diffusion route with/without nano sized dopants. The prepared YBCO is ball-milled for 10 hours with high speed followed by addition of dopants (Gd, BN) with different concentrations and their superconducting properties (critical temperature and critical current density, J_c) are investigated. Marked increase in the value of J_c is seen from measurement of critical current at 77K after the addition of Gd in the ball-milled YBCO. The high value of J_c, with Gd-doping indicates that the nano sized particles of the dopant are getting incorporated in the material. This is being confirmed with the studies of structural (XRD) and micro-structural (SEM) characterization to correlate with superconducting properties in order to understand the role of nano sized dopants in improving the current carrying capacity of superconductor. (author)