A current-biased contact between 0 and π Josephson junctions containing the spontaneous magnetic half-vortex is considered. It has been shown that under certain values of the external current (30–50 % less than the critical Josephson’s current far from the contact) this half-vortex becomes unstable with respect to transforming into the anti-half-vortex and creating a single Josephson-integer magnetic vortex which is to be swept away from the contact by the bias. A steady condition for a series of such events generation can be achieved for the single symmetrical contact. We suggest that these effects can be employed to identify the half-flux in an artificially made Josephson junction as well as in a granular superconductor. We also conjecture that the half-vortex can be utilized in superconducting memory and logic devices.

• Received 6 January 1995

DOI:https://doi.org/10.1103/PhysRevB.51.11965