激光系统的不稳定性及混沌

Instabilities and Chaos in Laser System

对于单模均匀展宽的行波激光器，利用海森堡方程，得到了描述Ｂ类激光器的Ｍａｘｗｅｌｌ－Ｂｌｏｃｈ方程组。利用计算机数值模拟的方法研究了泵浦参数受调制的情况。观察到一系列“正”的极限环与“倒”的混沌带的倍周期分岔序列，以及嵌在混饨带中的ｆ／３周期窗口，并计算了收敛常数δｎ。另外，在此模型里，大量存在由一个单一极限环的平凡吸引子到混沌的奇异吸引子的突变过程。还给出了部分参数区间的瞬态行为，其稳态虽然是单一的极限环运动，但暂态却随参数的改变呈现出准周期不稳定性及混沌的复杂运动形式。

The Maxwe1LBloch equations describing the class-B lasers were obtained by theHisonberg equation for the single-mode homogenously broadened travelling laser.The lasersystem,in which the modulated pump intensity was studied in detail.By numerical'calculation,the sequence of positive period-doubling vifurcation and the sequency of reversechaotic band were observed.In the chaotic band, some of the period windows were found.The temporary behavior of the system was in quasi-period instabilities and chaos motion. Insome regions of the parameters,the system lost its stabilities and directly transited into chaosfrom one limit cycle.