Anomalously large josephson switching currents in low dissipation josephson junctions

We have observed anomalously high values of the maximum switching current of Josephson junctions at temperatures where thermally activated switching was expected to drastically lower the maximum switching current. We show that these anomalously large switching currents are due to retrapping during the transition to the voltage state. We attribute this behavior to frequency dependent loading of the junctions by the package and readout circuitry. © 1989 IEEE