| In this thesis, the analysis of chaotic dynamics for several typical lasers is included. And the chaos control and chaos synchronization of lasers are studied. The main research work of this article has five parts as follows: First, the development history of laser and laser chaos theory is sum up. Chaotic dynamics can arise in several ways in semiconductor lasers, such as optical injection, external cavity feedback and directly modulation. The chaotic dynamic characteristics of semiconductor laser modulated by the three modulation ways above and the chaotic dynamic characteristics of single-mode CO2 laser with modulated cavity losses are deeper analyzed base on previous research; Moreover, the chaotic dynamics of the laser model of Lorenz-Haken and loss-modulated Nd:YAG laser are described simply. Second, the previous researches of laser chaos control and synchronization are summarized. The basic conceptions of chaos control and chaos synchronization are introduced. Especially, three typical control methods of laser chaos, such as delay feedback, external light injection and single mode control and three typical synchronization methods of laser chaos, such as optical injection feedback, optical coupling and chaos synchronization through reverse-phase are described. Third, we put forward the multiplicative sliding mode variable structure control scheme to control the chaotic motion of the semiconductor laser with external optical feedback .The advantage of this method is that the stable output laser can be obtained in a short time and the output power strength of the laser can be adjusted flexibly in accordance with the engineering requirement. Theory analysis and simulation results show that the results of the control have powerful stability and robust .Our research results have many helpful values to improve the speed of stable output, flexible adjustment of laser output power as well as efficiency of energy transformation for real laser system. Fourth, we raise the parametric adaptive control scheme to control the chaotic motion of a 1 .55μmdirectly modulated semiconductor laser. The advantage of this method is that the stable output laser can be obtained if only the controller was selected according to the control target. Our research results have many helpful values to improve the speed of stable output, flexible adjustment of laser output power as well as efficiency of energy transformation for real laser system. Fifth, the chaotic dynamics of Storage-Ring Free-Electron Laser is analyzed. Then, we propose a bi-directional coupled synchronization scheme with the stiffness of coupling varied periodically with the same frequency as that of the external modulation of system. Through this way two Storage-Ring Free-Electron Laser can be modulated to synchronization in a short time. We proof the possibility of synchronization by means of whether the ensemble average of the differential coefficient of Lyapunov function less than zero. Both numerical simulation and theoretic analysis show that synchronization of transmitter and receiver is feasible by this means. Our research results have many helpful values to chaos synchronization of two lasers, and possibility of performing secure, high-speed communications.
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