Globally exponential hyperchaos (lag) synchronization in a family of modified hyperchaotic Rossler systems

In this paper, we consider a new family of modified hyperchaotic Rossler systems, recently studied by Nikolov and Clodong using proper nonlinear feedback controllers. Particular attention is given to (i) globally exponential lag synchronization ( GELS) for tau > 0; and (ii) globally exponential synchronization (GES) for tau = 0. As a representative example, one system of the family of modified hyperchaotic Rossler systems is particularly studied, and Lyapunov stability criteria for the GELS and GES are derived via eight families of proper nonlinear feedback controllers. Moreover, we also present some nonlinear feedback control laws for other modified hyperchaotic Rossler systems. Numerical simulations are used to illustrate the theoretical results.