High temperature Josephson bicrystal junctions and arrays for metrologicalapplications

Concerning metrological applications of high-temperature superconductor (HT S) Josephson junctions, we investigated the properties of gold shunted bicr ystal YBCO junctions on yttria-stabilized zirconia (YSZ) and sapphire subst rates, We focus on three important items that are related to the problem of parameter spreads: (a) The control of the shunt resistance. This parameter is dominated by the contact resistivity between the YBCO and the hu. A dir ect method for the measurement of this crucial parameter was applied. (b) T he impact of the shunt resistance and the spread in junction resistance on the tolerable junction size and the frequency working regime for metrologic al arrays, And (c) the realization of series arrays with a high packing den sity of junctions using electron-beam-patterning. The parameter spreads are comparable to those of standard lithography processed junctions.