Distribution of flux pinning strength in a superconducting Bi-2223 silver-sheathed tape

The distribution of the flux pinning strength was estimated from a measured current-voltage curve for a monofilamentary Bi-2223 silver-sheathed tape i n a magnetic field parallel to the c-axis. It is found that the distributio n can be fitted well to the Weibull function of a very wide distribution. T his wide distribution seems to be caused by the low critical current densit y at weak links. The obtained Weibull function can be approximated fairly w ell by a simpler distribution function with which the scaling of current-vo ltage curves is analyzed using the flux creep-flow model. The obtained scal ing parameters agree well with the experimental results. (C) 1999 Elsevier Science B.V. All rights reserved.