In this letter, a spiral shape photonic crystal fiber (S-PCF) with nanocore has been suggested for the generation of the supercontinuum. The designing parameters have reformed to optimize the optical properties of the proposed structure. Finite element method is utilized to perform the numerical analysis of the proposed S-PCF. The proposed S-PCF exhibits a highly negative dispersion which ranges from − 82.21 to − 213.90 ps/(nm km) and high nonlinearity in the order of 6.31 × 10⁷ W⁻¹ km⁻¹ at the 1.55 µm wavelength. The birefringence of the proposed structure is zero at the 1.55 µm wavelength. Besides, effective area and field distribution are also described briefly.

中文翻译：

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高负色散纳米核螺旋光子晶体光纤，用于产生超连续谱

在这封信中，已建议使用具有纳米核的螺旋形光子晶体光纤（S-PCF）来产生超连续谱。设计参数已经过重新设计，可以优化建议结构的光学性能。利用有限元方法对所提出的S-PCF进行数值分析。所提出的S-PCF在1.55 µm波长处表现出高度负的色散，范围从-82.21到-213.90 ps /（nm km），并且具有很高的非线性度，约为6.31×10 ⁷  W ^-1  km ^-1。所提出的结构的双折射在1.55 µm波长处为零。此外，还简要介绍了有效面积和场分布。