求解梯度光纤模场的近似里兹-伽略金方法  

Approximate Ritz-Galerkin Method for Field Distribution of Graded-Index Optical Fibers

作　　者：王子华[1] 张辉[1] 肖中银[1] 

机构地区：[1]上海大学通信与信息工程学院,上海200072

出　　处：《光子学报》2006年第7期986-989,共4页Acta Photonica Sinica

基　　金：国家自然科学基金(60277025);上海市重点学科建设项目(T0102)资助

摘　　要：提出里兹-伽略金方法的一个近似或改进,即里兹-伽略金方法仅仅用来得到梯度型光纤的传播常量和纤芯中的模式场·包层场用修正贝塞尔函数以及已经求得的两个参量:包层径向衰减常量和场在纤芯-包层界面上的值重新构建·计算结果表明包层场准确度的改进是相当显著的,将这一近似方法应用于计算两根光纤之间的耦合系数,其结果与准确值几乎没有办法区分·Ritz-Galerkin method is used only for obtaining propagation constant and the radial mode field in core region of graded-index optical fibers. Cladding field has been constructed by using the accurate functional form （modified Bessel function） with two approximate parameters：the transverse decay constant in the cladding and the field value at core-cladding interface, which are already known. Numerical results show that the improvement on accuracy is significant. This approximate Ritz-Galerkin method has been applied to the calculation of coupling coefficient between two step-index optical fibers. Results are agreed well with exact values.

关 键 词：光纤光学 梯度型光纤 拉盖尔-高斯函数展开 模式场 耦合系数 

分 类 号：TN253[电子电信—物理电子学]