We report experimental and numerical studies of chaotic behavior in Josephson tunnel junctions driven by a train of picosecond electrical pulses. Dramatic changes were observed in both the experimental and simulated current-voltage characteristics, demonstrating that periodic wide-band excitations can temporarily alter the junction dynamics, leading to intermittent chaotic behavior. We relate the observed chaotic behavior to the junction switching processes in the regime of very short current pulses.

• Received 1 October 1987

DOI:https://doi.org/10.1103/PhysRevB.37.3778