Abstract
We report magnetic measurements on single crystals of . The magnetic critical current density in the Cu-O basal planes (1.5× A/ at 4.2 K) decreases exponentially with temperature as well as with field for K. This is ascribed to current tunneling through micro-Josephson-junctions. The behavior is radically different from that associated with macro-junctions typical of "granular" samples. It is argued that the anisotropy and the anomalous behavior of are connected with the dependence and the anisotropy of both the coherence length and the electron mean free path.
- Received 13 January 1988
DOI:https://doi.org/10.1103/PhysRevB.37.9792
©1988 American Physical Society