FLUX PINNING DUE TO NONSUPERCONDUCTING PARTICLES IN MELT PROCESSED YBACUO SUPERCONDUCTORS

While nonsuperconducting particles are known to serve as effective pinning centers in conventional superconductors, their effect in high T(c) superconductors is still controversial. In this paper, we give evidence that nonsuperconducting Y2BaCuO5 (211) inclusions can act as pinning centers in melt processed YBaCuO superconductors even when their size is orders of magnitude larger than the coherence length.