A Superconducting Sub-Structure in Sintered YBaCu₃O_7-x Plates

Abstract

We have measured magnetization of sintered YBa 2 Cu 3 O 7- x plates in a parallel magnetic field at 77 K. It was found that the difference Δ M in the magnetization between increasing and decreasing processes of the external field depends little upon the thickness of the plate, and it is predicted by the `critical-state' model that the difference is proportional to the thickness in a uniform specimen. The present experimental results suggest that the sintered plates consist of small superconducting sub-structures and that the superconducting connections among these sub-structures are not strong.