光子晶体光纤模式特征的研究

从基空间填充模出发，将光子晶体光纤的包层等效成均匀介质，从而将光子晶体光纤等效为阶跃折射率光纤。利用等效折射率模型，对光子晶体光纤的模式特征进行了详尽的研究，主要包括模式特性、传输常量、模场分布、功率限制特性、瑞利散射损牦特性、色散特性，等等。并通过功率限制因子这一参量将它与单模光纤进行比较。结果表明，光子晶体光纤单模工作波长范围比较宽，功率限制因子比较高，可用于制作更高抽运效率的光纤放大器。

The Mode Characteristics of the Photonic Crystal Fibers

The equivalent-refractive index model is implemented based on the fundamental space filling mode (FSM), the photonic crystal cladding is considered as a uniform medium, then the photonic crystal fiber is considered as a step index fiber. The mode characteristics of the photonic crystal fibers (PCF) are investigated in detail using the equivalent|refractive index model, including the propagation constant, the mode|field distribution, the power confinement factor, power loss and dispersion. With the PCF and SMF compared, it is shown that the PCF is almost an endlessly single|mode fiber. The PCF can be used to improve the pump efficiency of EDFAs because its power confinement factor is higher than that of the conventional erbium doped fibers.