| Controlling and synchronizing chaos are one of the most important problems in the field of nonlinear dynamics. Recently, Josephson junctions and photo-detectors have attracted much more attentions due to their extensive applications. Therefore, the investigations of control and synchronization of chaos in Josephson junctions and photo-detectors became a forward problem. The results of this dissertation establish good theoretical and experimental foundation for using their stable work states, utilizing Josephson junctions in the microwave secrecy communication, and applying and avoiding the chaos phenomena in the photo-detectors.This dissertation mainly investigates the control and synchronization as well as anti-control of chaos in resistive-capacitive-inductive-shunted Josephson junction (RCLSJJ). Then, for photo-detectors, its chaotic characters, chaos control, and chaos generation are also studied. The research work can been divided into four parts: controlling chaos in the RCLSJJ, synchronizing chaos in the RCLSJJ, anti-control of chaos in the RCLSJJ, and the investigation of chaotic features and chaos control as well as chaos generation in the photo-detectors.In part one, firstly, the dynamic equation of the RCLSJJ is deeply investigated, and the stability of its stable solutions is analyzed. Through the lyapunov exponent and the bifurcation diagram, the way and the process of generation chaos in the RCLSJJ are studied, and the parameter ranges of the periodic states and chaotic states are given. Secondly, four schemes of control chaos in the RCLSJJ are proposed, they are as follows: delayed linear feedback, delayed feedback, periodic signal control method and outer period signal parameter modulation method. For each scheme, the detailed numerical research process are given, good results are obtained, namely, these schemes all can effectively control chaos in the RCLSJJ into the different stable periodic states. In the third method, we analyze the influence of thermal noise on controlling chaos in the RCLSJJ for the first time, and the dynamical states of the RCLSJJ are contacted with its I-V curve so as to get its dynamical states directly.In part two, firstly, the generalized synchronization of chaos in two RCLSJJs is investigated by un-directionally coupling for the first time, and the auxiliary system approach has been used to detect the existence of this generalized synchronization state. Then, two schemes for completely synchronizing chaos in RCLSJJs are presented, which are taking autonomous chaotic system as driving system and taking non-autonomous chaotic system as driving system, respectively. We analyze in detail the process of realizing complete chaos synchronization, and give the law that the states of the driven systems vary with the driving system. For the first time, the complete chaos synchronization in RCLSJJs are realized by using the system that is different from response system as driving system.In part three, for the first time, two schemes are proposed for controlling the RCLSJJ from the periodic state into chaotic state, namely: modulating the critical current by using laser pulse and modulating bias current by using additive ac current realize anti-control of chaos in RCLSJJ, respectively. The numerical results show that these two schemes are effect, and the different chaotic orbits can been reconstructed by appropriately selecting the modulation amplitude and modulation frequency.In part four, firstly we analyze the process of generation chaos in the intrinsic photoconductor, and investigate the dependent relationship between the chaotic intermittent time interval and the relative parameter values. The result shows this time increases with reducing the concentration of traps; on the other hand, with increasing the rate of photo-excited charge carriers, this time can also been increased. Secondly, for the extrinsic photo-conductor p-Ge we discuss its manner of chaos generation, and present two schemes for controlling its chaos state, and they are controlling chaos by using periodic signal and controlling chaos in non-autonomous system by using the phase, respectively. The numerical investigations demonstrate the effect of these schemes. Finally, we realize anti-control of chaos in the extrinsic photo-conductor p-Ge by investigating the interaction between the chaotic laser and this photo-conductor.In the end, we briefly summarize our contributions, and discuss the future work according to the structural properties and applications of the RCLSJJ and photo-detector.
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