Observation of Josephson Junctionlike Behavior in Single-Crystal (Bi, Pb)₂Sr₂CaCu₂O_y

Abstract

The dependences of critical current on the temperature and magnetic field and the current-voltage characteristics in response to incident microwave radiation are measured in the direction of the c-axis of the 80 K superconducting phase (Bi, Pb)2Sr2CaCu2Oy bulk single crystal. Josephson junctionlike behavior is successfully observed, and it shows that the single crystal itself is composed of Josephson junctions along the c-direction and that its electrical transport in this direction is limited by intrinsic tunnel barriers existing in the single crystal.