High temperature superconducting Josephson junctions in a stacked bicrystal geometry

摘要

Bicrystal grain boundary Josephson junctions were fabricated in a stack of two layers of YB↓(2)Cu↓(3)O↓(x) separated by epitaxial SrTiO↓(3). Weak !ink behavior was observed in the bridges formed in both layers that had similar shunted-junction characteristics but significantly different critical currents. Characteristic voltages up to 1.9 mV were measured at 4.5 K. The resonant structure was seen in the current-voltage characteristics of the upper-layer junctions, and interactions between junctions in the two layers were evident. # 1997 American Institute of Physics. S0003-6951(97)00534-2