Manifestation of resonance-related chaos in coupled Josephson junctions

Manifestation of chaos in the temporal dependence of the electric charge is demonstrated through the calculation of the maximal Lyapunov exponent, phase–charge and charge–charge Lissajous diagrams and correlation functions. It is found that the number of junctions in the stack strongly influences the fine structure in the current–voltage characteristics and a strong proximity effect results from the nonperiodic boundary conditions. The observed resonance-related chaos exhibits intermittency. The criteria for a breakpoint region with no chaos are obtained. Such criteria could clarify recent experimental observations of variations in the power output from intrinsic Josephson junctions in high temperature superconductors.

► First demonstration of resonance-related chaos in CCJJ + DC model. ► Number of junctions in the stack strongly influence the fine structure in CVC. ► Strong proximity effect results from the nonperiodic boundary conditions. ► Chaos found to exhibit intermittency over a range of conditions and parameters. ► Observed chaos in model may help to explain recent experimental observations.