Critical Currents in [001] Grains and across Their Tilt Boundaries in YBa2Cu3O7Films

著者: J. Mannhart, P. Chaudhari, D. Dimos, C. C. Tsuei, T. R. McGuire - Physical Review Letters 1988 被引用: 420

The temperature and magnetic field dependences of the critical-current density of superconducting Y${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ films have been determined from transport measurements across individual [001] tilt boundaries and within single [001] grains. The results provide evidence that the basal-plane ${J}_{f}$ is limited by flux creep. In contrast, the $I\ensuremath{-}V$ characteristics and the temperature magnetic field dependences of the grain-boundary ${J}_{c}$ are consistent with a superconductor-normal-superconductor-type weak-link behavior. These results imply that the transport properties of these materials can be treated within a BCS framework.