折射率调制深度误差对多模啁啾光纤光栅光谱特性的影响  

The influence of index modulation depth errors on the spectral characteristics of multi-modes chirped fiber gratings

作　　者：赵佩[1] 钱凤臣[2,3,4] 赵保银[2] 

机构地区：[1]西北大学物理学系,陕西西安710069 [2]中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室,陕西西安710119 [3]中国科学院研究生院,北京100049 [4]西安通信学院2系,陕西西安710106

出　　处：《西北大学学报（自然科学版）》2012年第5期723-727,共5页Journal of Northwest University（Natural Science Edition）

基　　金：西北大学教学研究计划基金资助项目(KP08012)

摘　　要：目的对高斯切趾的多模啁啾光纤光栅存在折射率调制深度误差(包括横向误差和纵向随机切趾误差)时的光谱特性进行数值计算和分析。方法基于光栅中多模耦合的耦合模微分方程,将一种矩阵算法拓展用于求解多模耦合模微分方程。结果与理想无误差情况相比,折射率调制深度的横向误差使光谱反射峰宽度和峰值反射率减小,反射峰的位置向短波长方向偏移。折射率调制深度的随机切趾误差只有在幅度较大时才会使光谱反射峰产生明显分裂,频率较高的随机切趾误差几乎不改变多模光栅的光谱。结论这种矩阵方法在多模光纤光栅的光谱特性模拟分析中有较好效果,所得研究结果对多模光纤光栅的设计和制作有实际意义。Aim The spectral characteristics of apodized multi-modes chirped fiber gratings （MMCFGs） with index modulation depth errors, including transverse error and axial random apodized error, are calculated and studied the- oretically. Methods Based on coupled mode equations, an matrix calculating method is extended to solve the mul- timode coupling differential equations. Results The transverse error affects the spectrum characteristics of MMCFG. With transverse error, the MMCFG decreases the reflectivity and the width of its reflection peaks, and shifts the reflection peaks toward shorter wave lengths. In comparison with the desirable condition, the low frequen- cy random apodized error with large amplitude causes the spectrum splitting, whereas the high frequency error does not change the spectrum characteristics. Conclusion The extended matrix method shows better effects in simula- ting of MMCFG＇s spectrum characteristics, and the results have practical significance in fabrication and design of MMCFG.

关 键 词：多模啁啾光纤光栅 折射率调制深度 横向误差 随机切趾误差 

分 类 号：TN253[电子电信—物理电子学]