Generalized control and synchronization of chaos in RCL-shunted Josephson junction using backstepping design

This paper generalizes the control and synchronization of chaotic dynamics in resistive-capacitive-inductive-shunted Josephson junction (RCLSJ) models via the backstepping nonlinear control theory. The method, which consists in a recursive approach that interlaces the choice of a Lyapunov function with the control, is used to design a generalized control function that is capable of controlling the chaotic dynamics exhibited by RCLSJ model to track desired dynamics. The result suggests that the generalized controller could be used as a device for tuning the junction signal into any desired form. The active backstepping technique is used to design a single control function that achieves generalized projective synchronization between two RCLSJ systems evolving from different initial conditions. This result suggests that the controller for generalized projective synchronization could be used to amplify the junction signal. Numerical simulation results show that the generalized control functions are effective in both the tracking control and generalized projective synchronization of RCLSJ models. (C) 2010 Elsevier B.V. All rights reserved.