Strongly coupled high Tc edge junctions

Abstract We report the fabrication of high T c edge junctions with high critical current densities. They carry Josephson currents up to 83.5K, just below the T c of the electrodes. The magnetic field dependence of the critical current shows conventional sinc function like modulation just below T c . At lower temperatures the junctions are so strongly coupled that they are large compared to the Josephson penetration depth, and show the long junction behaviour seen previously in low T c superconductors.