Control system approach to the dynamics of nonidentical Josephson junction systems

The dynamics of a resistively coupled nonidentical Josephson junction (JJ) circuit is explored and a new control strategy is applied in order to smoothen the unstable regimes. In such a system, periodic, quasiperiodic and chaotic behaviors have been encountered worldwidely. In addition, the existence of the hyperchaos has also been declared by Kurt and his coworker. It is understood that the dynamic features strictly depend on the coupling resistance Rcp. Indeed the decrease in Rcp causes a sudden increase in Lyapunov exponents, which prove the chaoticity of the system. Since a wide chaotic region is encountered, the control of the system becomes important for a number of engineering applications. A new control system approach has been applied in order to solve this problem.