Fig. 1. The sixfold photonic quasi-crystal fiber: (a) Cross-section of SPQCF; (b) index profile of SPQCF.六重准晶涡旋光光子晶体光纤　(a)光纤端面图; (b)折射率分布图

Fig. 2. Intensity and polarization of vortex beams in SPQCF.光子晶体光纤中涡旋光强度分布以及偏振分布

Fig. 3. (a) Effective refractive indices; (b) effective index difference as a function of wavelength for vector modes in SPQCF.(a)模式有效折射率( ); (b)模式间有效折射率差( )随波长的变化曲线

Fig. 4. Confinement loss as a function of wavelength for HE₂₁ mode with different r₀, the inset shows the loss between 1500−1600 nm. HE₂₁模的限制性损耗随波长的变化(不同中心空气孔半径), 插图为1500—1600 nm波段内HE₂₁模的限制性损耗

Fig. 5. Dispersion as a function of wavelength for with different , the inset shows the flat trend with di-fferent 模色散系数随波长的变化(不同中心空气孔半径), 插图为 对涡旋光平坦趋势的影响

Fig. 6. (a) Effective mode area of HE₂₁, (b) nonlinear coefficient as a function of wavelength for HE₂₁ mode with different r₀, the inset shows the (a) effective modes area and (b) nonlinear coefficient between 1500−1600 nm. (a) HE₂₁模的模场面积; (b) HE₂₁模的非线性系数随波长的变化 (不同中心空气孔半径); (a), (b) 的插图分别为 波段内的模场面积和非线性系数

Fig. 7. as a function of wavelength for vortex modes in SPQCF. 光纤中不同本征模的 随波长的变化