Dynamics Of Nonlinear Optical Phenomena Based On The SBS System

The nonlinear dynamical phenomena of laser system have attracted a great deal of interests of scientists since the optical chaos behaviors and rogue wave were observed. Physical understanding of these nonlinear systems has been boosting during the recent years by the investigations carried out with various laser systems. Because there is a possibility of being used in the chaos-based security communication and in the fast random bit generation for the chaotic systems, the interesting subjects of the chaotic systems have been dominating the theories and applications. The critical work in controlling chaos is the observation of bifurcation route in the chaotic process generation in which trajectory has been embedded in a large number of unstable periodic orbits. During the last decades, the experiments of various bifurcation routes have been exhibited in laser systems, such as from a period-three cycle or a period-doubling to chaotic process.In the nineties of last century, chaotic stimulated Brillouin scattering (SBS) in optical fibers with weak external optical feedback has been investigated experimentally and theoretically by the British scientists.However, only the bifurcation route to chaos through period-one and quasi-periodic emission was discovered in the former work because the chaotic domain is very short in the general nonlinear system.In order to control the chaos process and observe finer periodic-orbit structures, a novel experiment was designed to extend the chaotic domain by using long optical fibers in the SBS system. In this experiment, the period-one, period-doubling, period-four and period-eight cycle routes to the chaos laser process as well as the more details of chaos, have been observed. Moreover, excitation of intense periodic quasi-optical rogue waves in a stochastic background by continuous-wave stimulated Brillouin scattering in long optical fibers with weak feedback is investigated. And the observed waves are also fairly well described by a three-wave coupling theoretical model for the SBS with weak pump feedback.