外部光注入DFB-LD的非线性动力学系统

外部光注入DFB-LD的非线性动力学系统

摘要：在介绍非线性科学和混沌的基础上，基于DFB半导体激光器原理，建立理论模型并实验研究证实外部光注入DFB激光器将输出众多的非线性动力学行为特征，理论模型和试验结果在外部光注入和频率失谐条件下具有良好的偶合效果。本文给出了其输出特性随注入光强度和频率失谐量变化的1系列动力学特征图。实验结果表明：激光器的动力学行为对外部的微扰10分敏感；在不同外部光注入或频率失谐条件下，激光器可以呈现出多种非线性动力学特征。文章最后给出了外部光注入下DFB激光器非线性动力学状态分布图；当激光器处于复杂动力学区域时，其频谱为连续谱；在连续谱上存在多个明显的峰，其对应的频率定义为特征频率，特征频率的大小与注入光的强弱以及频率无关。
关键词：非线性动力学；混沌；DFB半导体激光器；外部光注入；失谐频率

The nonlinear dynamics of a distributed feedback semiconductor laser subjected to external optical injection

Yang Qi
Physics School of Science and Technology,Southwest University,Chongqing,400715,China

Abstract: In this paper firstly introduced the nonlinear science and chaos. Then a theory model based on the principle of DFB-LD has been presented. A comparison of the observed characteristics with the predictions of a coupled rate-equation model shows quantitative agreement over a wide range of injection parameter or the detuning frequency. The nonlinear dynamic characteristics of distributed feedback (DFB) semiconductor lasers subject to external optical injection have been investigated experimentally. The output dynamical characteristics are mapped as a function of the power of optical injection and the detuning frequency. Experimental results show that DFB semiconductor laser is very sensitive to external perturbation and can exhibit various nonlinear dynamical characteristics when subjected to different external optical injection. In the end of this paper we presented the mapping of the nonlinear dynamics characteristics of DFB-LD subject to external optical injection. When the laser exhibits complex dynamic, its spectrum is continuous, and there are several peaks in the spectrum. The magnitude of the frequency that the peaks correspond to respectively has nothing with the power and the frequency of injection field.

1、绪论
1.1 引言
2O世纪6O-7O年代建立的非线性科学是自然科学的重大发展。1些物理学家认为非线性科学是2O世纪物理学继相对论、量子力学之后的第3次科学革命。非线性科学的诞生标志着人类对自然界的认识由线性进入非线性领域，揭示了自然界存在着更普遍的、既确定又随机的混沌现象及其特有的非线性规律[1]。
什么是非线性科学呢?线性表示量与量之间成正比关系，其部分之和等于整体，描述线性系统的方程遵从叠加原理；非线性指整体不等于部分之和，叠加原理失效[3]。数学上,主要通过对算子的分析来讨论线性和非线性。如果1个算子L满足: