多偏振控制高双折射光纤环形镜输出特性的理论和实验研究

The transmission characteristic of the multi-polarization controlled fiber loop mirror

针对光纤环形镜(FLM)在单偏振控制下波长间隔不可调等缺点,对多偏振控制FLM的输出特性进行了理论和实验研究.用Jones矩阵法分析了单偏振、双偏振和三偏振控制FLM的透射谱,研究发现:相比单偏振控制FLM,多偏振控制FLM具有波长间隔可调和边频抑制等特性;透射谱的偏振可调性随偏振控制级数的增加而增强,实验结果与理论研究一致.实验中利用双偏振控制FLM作为波长选择的光纤激光器输出激光的边模抑制比较采用单偏振控制FLM时提高了近5dB.

The multi-polarization controlled fiber loop mirrors （FLMs） are presented and their characteristics are studied,because of the non-tunable characteristic of the wavelength interval for single-polarization controlled FLM.The multi-polarization controlled FLMs are studied theoretically with the Jones matrix.We experimentally study the single-,double-and triple-polarization FLMs,and the results show that compared with the single-polarization controlled FLM,the multi-polarization controlled FLM possesses the interval tunability and the side-frequency restriction are shown.The experimental results are in good agreement with theoretical results.The side-frequency restriction characteristic is shown in a ring fiber laser of double-polarization FLM and the side-mode suppression ratio is enhanced by 5 dB compared with the one of single-polarization FLM.