Tunneling characteristics of internal Josephson junctions in YBa sub 2 Cu sub 3 O sub (7-delta) thin films.

We have measured detailed I-V characteristics of small areas of YBa sub 2 Cu sub 3 O sub (7-delta) films, which exhibit structure associated with individual Josephson junctions within the film. Both hysteretic and non-hysteretic junctions are seen. A simple model relating the voltage steps to the junction properties is developed. The temperature dependence of I sub e for the hysteretic junctions fits that predicted for quasiparticle tunneling junctions between conventional superconductors.