基于新型层状微结构光纤的模式截止特性分析(英文)

Modal cut-off in a novel photonic crystal fiber with layered microstructures

采用矢量有限元法分析和设计了一种新型的层状微结构光子晶体光纤.通过数值模拟纤芯基模的有效折射率neff和包层空间填充基模有效折射率ncld,获得这种微结构光纤的模式截止特性.与传统光子晶体光纤相比,这种微结构光纤单模和多模的边界条件在获得无截止单模传输前提下,具有更大的空气孔尺寸和非线性效应,有更高的灵活性,可以保持更短的单模截止波长,获得较高的非线性系数.

A novel photonic crystal fiber （PCF） with layered microstructures was designed and investigated by the vector finite element method. The modal cut-off property of this novel fiber was evaluated by simulating the effective index neff of the fundamental mode in the core and the effective index ncld of the fundamental space-filling mode in the PCF with layered microstructures. Furthermore, the single/multi-mode boundary was demonstrated and fitted in a numerical equation. Compared with that of traditional PCF, this novel PCF had a larger hole-diameter with the endlessly single-mode. And the nonlinear coefficient of the novel PCF was also investigated in details. The improved single/muhi-mode boundary can be helpful in the design of nonlinear PCF to maintain the endless single mode property.