TRANSIENT CHARACTERISTICS BETWEEN PERIODIC ATTRACTORS STABILIZED BY CHAOS CONTROL IN A SEMICONDUCTOR LASER

Abstract

We investigate the transient response time between periodic attractors stabilized by chaos control methods in a semiconductor laser. We use the revised occasional proportional feedback (ROPF) method to shorten the transient response time and compare it with the high frequency injection (HFI) method. A chaotic attractor is stabilized resulting in two different periodic attractors (period-1 and period-6) under different control parameters, and the transient response time is measured as one of the stabilized periodic attractors is switched to the other. During the transition, the trajectory approaches a certain unstable periodic orbit (UPO), and the distance between the trajectory in the phase space and the UPO can be described as an exponential function of the transient response time. Since the trajectory can directly converge into the periodic orbit by using the ROPF method, the transient response time obtained by the ROPF method can be shortened more than that obtained by the HFI method.