本文对发射波长为1.3 μm,具有不同脊形波导宽度InGaAsP激光器的TE、TM模偏振输出特性进行了测量.实验观察到脊形波导比较窄的器件具有TE、TM模竞争现象,而脊形波导比较宽的器件在阈值电流以上,只有TE模激射,没有模式竞争.利用偏振度概念计算了阈值电流以上和阈值电流以下的偏振度,并对其进行了讨论.本文指出,只要严格选择激光器的参数,并控制环境温度,合理使用器件,就可获得稳定的偏振输出,而不必使用任何起偏系统.

Thepolarization characteristics of TE, TM modes output from the 1. 3 μmInGaAsP/InP lasers with different ridge-waveguide width are measured. It is observed that there is the polarization competition between TE and TM modes in narrow ridge-waveguide laser. For wider ridge-waveguide laser,the polarization of the stimulated emission above threshold current exhibits only TE mode, there is no competition. The degree of polarization above and under threshold currents are calculated and discussed. The results show that it is possible to get stable polarization output if we choise strictly the parameters of the laser, control the evironmental temperature and rationaly use the devices, and it is not necessary to use any polarizer.