Josephson junction circuit model and its global bifurcation diagram

Abstract In order to understand the meaning of a typical Josephson junction, we introduce a circuit model which can be used to describe the dynamical behavior of the junction under the exciting of radio-frequency current. The global bifurcation diagram of the Josephson junction is demonstrated with a computer simulation. Through the diagram we observe the complex and rich dynamics of the junction, e.g. bifurcation, phase-locking, and chaos. The relation between motion and symmetry breaking is also discussed.