ENHANCEMENT OF TRANSPORT CRITICAL-CURRENT DENSITIES IN (BI,PB)2SR2CA2CU3O10AG TAPES AT 77-K FOLLOWING FAST-NEUTRON IRRADIATION

We report on significant enhancements of the transport critical curren t densities J(c) in (Bi,Pb)2Sr2Ca2Cu3O10/Ag tapes at 77 K and higher m agnetic fields after neutron irradiation. This enhancement is attribut ed to an improvement in the flux pinning capability of this material b y the neutron-induced defects. The angular dependence of J(c) is still consistent with two-dimensionality, i.e., flux pinning of pancake and /or Josephson vortices is directly confirmed by this transport measure ment. Fast neutron irradiation also affects the weak links in a way wh ich agrees with previous results on unaligned ceramics. However, there are some peculiarities which need further investigation. (C) 1994 Ame rican Institute of Physics.