CRITICAL-CURRENT DENSITY DISTRIBUTION IN SUPERCONDUCTING OXIDE LAYER OF BI2SR2CACU2OX AG COMPOSITE TAPES/

The relationship between J(c) and the thickness of the oxide layer of Bi2Sr2CaCu2Ox/Ag composite superconductor is studied to clarify the cr itical current distribution in the oxide layer. J(c) of the oxide laye r within 5 mu m from the oxide/silver interface exceeds 3 X 10(5) A/cm (2) at 4.2 K, 10 T, while J(c) for the whole part of oxide (25 mu m in thickness) stays at 1.2 x 10(5) A/cm(2), The results indicate that th e superconducting current is carried by thin and highly aligned oxide part along the oxide/silver interface. The results also suggest that t he higher J(c) can be expected with decreasing thickness of the oxide layer and with increasing the oxide/silver interface. (C) 1998 Elsevie r Science B.V. All rights reserved.