FABRICATION OF CAPACITIVELY SHUNTED HIGH-TC JOSEPHSON-JUNCTIONS

Hysteretic high Tc Josephson junctions were fabricated by shunting gra in boundary YBa2Cu3O7 junctions with a monolithic Au film capacitor. T he junctions were made by pulsed laser deposition with ion milling, an d the shunt capacitor by rf sputter deposition and lift-off. The McCum ber parameter beta(c) obtained from the measured current-voltage curve s was much smaller (<6) than the calculated values (3x10(3)-3x10(4)). The discrepancy is believed to be due to that the series resistance of the Au film dominates the capacitive reactance in the high voltages a nd thus reduces the hysteresis. Full hysteresis will be realized by re ducing the series resistance.