反向保偏光纤耦合器偏振特性研究

Research of polarization characteristics of reverse polarization-maintaining optical fiber coupler

为了提升高能偏振光纤激光器输出激光偏振态稳定性,通过阐述反向保偏光纤耦合器反向消光比基本原理,采用信号光源与(6+1)×1反向保偏光纤耦合器研制相结合,取得了反向保偏光纤耦合器信号保偏光纤直径、信号保偏光纤应力区物理变化等因素和反向保偏光纤耦合器反向消光比的关系。结果表明,信号保偏光纤直径越小,输出偏振激光的偏振态越稳定,反向消光比大于49 dB,同时促进反向保偏光纤耦合器抽运光纤臂耦合效率提升至98%以上;正向偏振激光输出光纤应力区物理结构变化越明显,经反向保偏光纤耦合器反向输出偏振激光的偏振态越不稳定。该研究可为制备高消光比、高能偏振光纤激光器提供参考。

In order to improve the output laser polarization stability of high-energy polarization fiber lasers,the signal light source and(6+1)×1 reverse polarization-maintaining optical fiber coupler were combined by introducing the basic principle of reverse extinction ratio of reverse polarization-maintaining optical fiber coupler.The influence of signal polarization-maintaining optical fiber diameter and physical change of the stress area of the reverse polarization-maintaining optical fiber on the reverse extinction ratio of a reverse polarization-maintaining optical fiber coupler was studied.The results show that the smaller the diameter of the signal polarization-maintaining fiber,the more stable the polarization state of the output polarized laser,and the reverse extinction ratio is greater than 49 dB.At the same time,the coupling efficiency of the pumping fiber arm of the reverse polarization-maintaining fiber coupler is improved to more than 98%.The more serious the change of the physical structure of the stress region of the forward polarization laser output fiber,the less stable the polarization state of the output polarization laser.The research provides reference for the preparation of high extinction ratio high-energy polarization fiber lasers.