The measurement of Josephson current of double Josephson junction

摘要

We have investigated the relation between the Josephson current and the thickness of Nb middle layer of double Josephson junction. The characteristic of the sample is somewhat different even though the sample is made on the same condition. So we have changed only the thickness of Nb middle layer of the double Josephson junction on the same substrate with the shutter between the sample and the target. We fabricated the double Josephson junction completely on the same condition except for thickness of Nb middle layer. Josephson current has increased as Nb middle layer is thin.. However, no Josephson current was observed without Nb middle layer.