Magnetic field dependence of Josephson current by applying the external magnetic field perpendicular to the Josephson junction

Abstract

The hysteresis of the Josephson current to the external magnetic field Hz perpendicular to the Josephson junction is reported. We have measured the magnetic field Hz dependence of the Josephson current of the Nb∕Al-AlOx∕Nb junction. The Josephson current decreases with oscillating as the magnetic field Hz was increasing. When the magnetic field Hz was applied more than 2800[A∕m], the Josephson current became 0. Even if the magnetic field Hz was decreased from 2800[A∕m] to 0, no Josephson current was observed. The Josephson current exhibited hysteresis to the external magnetic field Hz.