TRANSPORT-PROPERTIES IN TL-BA-CA-CU-O GRAIN-BOUNDARY JUNCTIONS ON SRTIO3 BICRYSTAL SUBSTRATES

We have investigated the electrical properties of TI-Ba-Ca-Cu-O high-T(c) superconductor bicrystal grain boundary junctions. The behavior of the transport parameters is very similar to those obtained in YBaCuO7-delta junctions. In particular, the temperature dependence of the critical current and the scaling behavior of the critical current density as a function of the misorientation angle were analyzed. Relatively good control of the transport parameters as a function of the misorientation angle has been achieved. The current-voltage characteristics showed a resistively shunted junction model-like behavior at large angles (theta greater-than-or-equal-to 20-degrees); at lower angles, the characteristics were more flux-flow like. Preliminary results on noise characteristics are also presented.