EFFECTS OF SURFACE HEAVY-ION IMPLANTATION ON AG BSCCO-2223 TAPES/

In this paper the effects of surface 0.25 GeV Au ion implantation on t he superconductive properties of Ag/BSCCO-2223 tapes are studied. Colu mnar-defect length was similar to 5% of the whole sample thickness. St rong localisation phenomena and the occurrence of the localisation cha racteristic kink in the irreversibility line, IL, are observed at a po int phase (B-kink, T-kink). Large shift of this line towards higher fi elds and temperatures and a very substantial enhancement of the critic al current density, J(c), have been found. IL anisotropy and J(c) anis otropy of the irradiated samples are switched off up to fields higher than B-kink. The characteristic trends, as well as their dose dependen cies, are particular of such pinning strategy. The results give useful hints for further improvement of the Bi-2223 tape technology, concern ing the introduction and influence of appropriate surface pinning. (C) 1998 Elsevier Science S.A. All rights reserved.