八边形结构的双折射光子晶体光纤

提出一种新型的双折射光子晶体光纤，在正八边形的基础上改变纤芯附近的几个空气孔的直径产生双折射.利用多极法对该光纤基模的模场分布、色散、限制损耗及双折射特性进行数值分析，并且分析了一些参数对双折射的影响.计算了具有相同参数的六边形结构光子晶体光纤的色散系数、限制损耗及双折射率.研究表明，具有相同参数的八边形结构光子晶体光纤比六边形结构光子晶体光纤的双折射率明显提高，限制损耗大幅度减小，零色散波长也向短波方向移动. 关键词： 光子晶体光纤 双折射 色散 限制损耗

Octagonal photonic crystal fiber of birefringence

In this paper we propose a novel octagonal birefringent photonic crystal fiber, which shows birefringence when the size of several holes near the core is enlarged. The modal field, dispersion, confinement loss, birefringence of the fiber fundamental mode and the influence on bireffingence of some parameters are simulated by multipole method. The dispersion, confinement loss,bireffiagence of the hexagonal photonic crystal fiber having the same parameters were also computed. By comparision, we conclude that the octagonal photonic crystal fiber have larger birefringence, smaller confinement loss and shorter wavelength of zero dispersion than the hexagonal photonic crystal fiber with the same parameters.