椭圆芯光子晶体光纤的偏振特性

采用全矢量模型研究椭圆芯光子晶体光纤(photonic crystal fibers,PCFs)的偏振特性。研究表明：椭网芯PCF基模的两个正交偏振态不再简并,模场具有较强的线偏振特性;模式双折射可达10^-3量级,该数值比传统椭圆保偏光纤至少高一个量级;在比传统椭圆保偏光纤更长的波长处获得零走离点和负走离区。椭圆芯PCF的偏振特性与光纤结构参数有较强的依赖关系,通过适当选择光纤的相对孔径和孔距,有望在给定的波长上实现高双折射和零走离单模运转,或设计出高双折射、大走离的单模光纤,为研制高性能保偏光纤提供了一个新的途径。

Polarization Properties of Elliptical Core Photonic Crystal Fiber

The polarization properties of elliptical core photonic crystal fibers(PCFs) were investigated with the full vector model.According to the numerical result,the two orthogonal polarized states of the fundamental mode become non-degernerate in the elliptical core PCFs and appear strongly linear polarization.The modal birefringence can attain the order of 10-3 that is at least one order of magnitude higher than that of conventional elliptical polarization-maintaining fibers.A zero walkoff point and a negative walkoff region occur at the longer wavelength region in this PCF.The polarization properties are strongly dependent on structural parameters of this PCF.This offers the possibility that the single mode operate at high birefringence and zero-walkoff at a given wavelength or at high birefringence and large walkoff through choosing a suitable relative hole diameter and hole pitch.A new way is proposed for fabricating polarization-maintaining fibers with high performance.