熔锥型单模光纤耦合器的一致性模型  

A United Model of Fused Single-mode Fiber Coupler

作　　者：任建国[1] 胡永明[1] 张学亮[1] 胡正良[1] 

机构地区：[1]国防科技大学光电科学与工程学院,长沙410073

出　　处：《半导体光电》2011年第1期18-23,共6页Semiconductor Optoelectronics

摘　　要：由于熔锥型光纤耦合器几何形状的特殊性,其耦合特性的研究通常是对于不同的区域采用不同的近似模型。构建了一个可以同时对耦合器各个区域耦合特性进行仿真的一致性模型。选取适当的连续函数描述锥形曲线和横截面形状;采用归一化的三角分布和高斯分布的加权叠加实现了模场沿耦合器各区域的连续变化。利用变分法和局部模式理论,推导出了耦合器任意位置处的耦合系数计算公式。该模型考虑了熔融区的纤芯效应,考虑了锥形区的耦合效应,是一个更为精细的理论模型。数值模拟结果显示,该模型可为光纤耦合器和波分复用器的制作提供理论指导。Generally, coupling characteristics of a fused single-mode fiber coupler are studied in its different zones with separate approximate models because of its special geometrical shape. In this paper, a united model was built to simulate the coupling characteristics of each zone of the coupler simultaneously. Some appropriate continuous functions were chosen to describe the tapered curve and the transverse cross section. The mode-field distribution in the coupler was obtained by the weighted superposition of normalized triangular distribution and normalized Gaussian distribution. Some formulas for calculating the coupling coefficients of the coupler anywhere were deduced based on the variation technique and the local mode theory. The effects of the fiber-cores in the fuse zone and the coupling effects in the taper zones were considered. Simulation results indicate that it is a more accurate model that can be used to guide the practical design and fabrication of fiber couplers and WDMs.

关 键 词：光纤耦合器 耦合特性 变分法 局部模式 一致性模型 

分 类 号：TN253[电子电信—物理电子学]