Magnetic Properties and Current-Voltage Characteristics of Anisotropic Y1Ba2Cu3O7-y / Native Barrier / Pb Josephson Planar Tunnel Junctions

The magnetic properties and the current-voltage characteristics of Y1Ba2Cu3O7-y(YBCO) / native barrier / Pb Josephson tunnel junctions employing both the c-axis- and a, b-axes- oriented YBCO films are reported. The stable Fraunhofer-like patterns of Josephson critical current under the applied magnetic field are observed. The current-voltage curves of the junctions made of a, b-axes-oriented YBCO films exhibit hysteretic behavior typical of conventional Josephson tunnel junctions. The anomalous temperature dependence of Josephson critical current is also reported.