半导体环形激光器的混沌同步及优化

Chaotic Synchronization and Optimization of Semiconductor Ring Lasers

数值模拟了半导体环形激光器(SRLs)的同步.在频率失谐为-20 GHz,注入系数大于2.5时,两种方案(闭环、开环)的SRLs均可以获得互相关系数大于0.95以上的同步.讨论了在不同的注入系数下同步对频率失谐的稳健性,结果表明开环同步对频率失谐的稳健性更好。研究了SRLs内部参数的变化对同步的影响,通过适当调节SRLs内部参数的数值可使两种结构的同步质量都得到优化。闭环同步的互相关系数从0.96提高到0.99(开环同步互相关系数从0.95提高到0.97)。最后讨论了在闭环结构中偏置电流和反馈延迟时间失谐对同步的影响。

Synchronizations of semiconductor ring lasers are investigated numerically. When the frequency mismatch is-20 GHz and the injection coefficient is greater than 2.5, the semiconductor ring lasers in two different configurations（open and closed loops） can all achieve good synchronizations with cross correlation coefficient above 0.95. The robustness of two schemes to frequency detuning with different injection coefficients are discussed and the results show the robustness of open loop structure are better than that of closed loop structure. The influences of internal parameters′ mismatches on the chaos synchronization are also studied. The synchronization of two structures can be optimized by choosing appropriate internal parameters. The correlation coefficient of closed loop increases from 0.96 to 0.99（0.95 to 0.97 about open loop）. At last the impacts of the feedback delay time and bias current on the synchronization in the closed loop structure are analyzed.