光纤光栅外腔半导体激光器的多参量优化分析

采用多参量优化的多目标遗传算法优化了光纤光栅外腔半导体激光器（FGECL）管芯的两个端面反射率和外腔长度.研究了FGECL的阈值特性，并对多个参量优化和单个参量优化的结果进行了比较分析.表明获取最低阈值电流，要以激光器的电光转换效率和输出光功率为代价，从而得到高边模抑制比、窄光谱线宽、良好动态特性和高调制速率的FGECL.并且发现当两端面的反射率增加，同时激射波长在外腔长度中形成稳定谐振时，激光器的阈值电流达到最小值，但相应的电光转换效率和出光功率会急剧地减小.

Analysis of a Fiber Bragg Grating External-Cavity Semiconductor Laser by Multi-parameter Optimization

Based on the equivalent cavity model, the threshold characteristics of an fiber grating external-cavity semiconductor laser (FGECL) are investigated by the multi-parameter optimization of two antireflection and high reflection coatings, and the external-cavity length, and the results of the multi-parameter optimization are compared with that of the single-parameter optimization. To obtain the lowest threshold current needs the cost of the reduction of the slope efficiency (namely, the efficiency of electro-optical conversion) and the power of the output light so that the FGECL is of high side-mode-suppression-ratio (SMSR), narrow line-width, excellent dynamic property and high modulation rate. Also it is found that when the reflectivities of two antireflection and high-reflection coatings increase, and the stable oscillation of the master wave is established in the external cavity, the threshold current is the lowest, but the efficiency of the electro-optical conversion and the power of the output light reduce sharply.