The dissipation in the high Tc ceramic superconductor La 1.85Sr0.15CuO4- delta is interpreted in terms of interacting magnetic flux systems: vortices in the ceramic grains and fluxons between them. In zero field cooling experiments the dissipation shows a sin2 Theta dependence, where Theta is the angle between current and field. This result and the existence of an angle independent critical current are analyzed in the framework of a granular system where the dissipation is due to two contributions, one induced by movement of magnetic flux and the other associated to dissipation in the junctions.
All Science Journal Classification (ASJC) codes
- Ceramics and Composites
- Condensed Matter Physics
- Metals and Alloys
- Electrical and Electronic Engineering
- Materials Chemistry