Numerical Simulations of the Fluxon Dynamics of a Two-Dimensional Josephson Junction System

A direct perturbation method applied to a long Josephson junction molded by one-dimensional sine-Gordon equation is presented and the modulation of perturbations on fluxon velocity and stable state is studied. Simulations of a two-dimensional Josephson junction with dc bias current in an external magnetic field provide an I–V characteristic curve for the system and determine the various dynamic behaviors, including the periodic, quasiperiodic, and chaotic motions. Physical explanations for the behaviors are presented. The numerical results are in good agreement with the energetic analysis.