Chaotic Dynamics of a Josephson Junction with a Ratchet Potential and Current-Modulating Damping
- 69 Downloads
The chaotic dynamics of a Josephson junction with a ratchet potential and current-modulating damping are studied. Under the first-order approximation, we construct the general solution of the first-order equation whose boundedness condition contains the famous Melnikov chaotic criterion. Based on the general solution, the incomputability and unpredictability of the system’s chaotic behavior are discussed. For the case beyond perturbation conditions, the evolution of stroboscopic Poincaré sections shows that the system undergoes a quasi-periodic transition to chaos with an increasing intensity of the rf-current. Through a suitable feedback controlling strategy, the chaos can be effectively suppressed and the intensity of the controller can vary in a large range. It is also found that the current between the two separated superconductors increases monotonously in some specific parameter spaces.
KeywordsJosephson junction Ratchet potential Melnikov function Chaos
This work was supported by the Natural Science Foundation of Hunan Province (2016JJ6020) and the Scientific Research Fund of Hunan First normal University (XYS13N16).