Abstract:

We performed magnetic moment (m) relaxation measurements at low temperatures (5 less than or equal to T less than or equal to 20 K) in two single phase, c-axis-oriented polycrystalline Bi1.7Pb0.3Sr2Ca2Cu3O10+delta (2223) samples prepared under different conditions with different T-c's. The m versus t data show a logarithmic relation and by fitting them the J(c)(H, T) and U-c(H, T) variation were extracted. (C) 2000 Elsevier Science B.V. All rights reserved.