Oscillations of Josephson Supercurrent in Pb/Al/AlO_x/Pb Junctions

Abstract

Osccillations of the Josephson supercurrent have been observed in Pb/Al/AlOx/Pb junctions. The oscillations only occur in the temperature dependence of the supercurrent in a constant magnetic field. Causes for these oscillations are discussed in terms of the change of the London penetration depth and the Josephson penetration depth with temperature.