The study reports on the design and performance of two air‐filled and two partial ethanol‐filled photonic crystal fiber (PCF) structures with a tetra core for supercontinuum generation. The PCFs are nonlinear with ultra‐flattened zero dispersion. Holes with smaller areas are used to create a tetra‐core PCF structure. Ethanol is filled in the holes of smaller area while the larger holes of cladding region are air‐filled. Optical properties including dispersion, effective mode area, confinement loss, normalized frequency, and nonlinear coefficient of the designed PCF structures are investigated via full vector finite difference time domain (FDTD) method. A PCF structure with lead silicate as wafer exhibits significantly better results than a PCF structure with silica as wafer. However, both structures report dispersion at a telecommunication wavelength corresponding to 1.55 μm. Furthermore, the PCF structure with lead silicate as wafer exhibits a very high nonlinear coefficient corresponding to 1375 W⁻¹ km⁻¹ at the same wavelength. This scheme can be used for optical communication systems and in optical devices by exploiting the principle of nonlinearity.

中文翻译：

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产生超连续谱的超平坦零色散非线性光子晶体光纤的设计

该研究报告了两个具有四芯核的空气填充和两个部分乙醇填充的光子晶体光纤（PCF）结构的设计和性能，用于产生超连续谱。PCF是非线性的，具有超平坦的零色散。面积较小的孔用于创建四核PCF结构。乙醇填充到面积较小的孔中，而覆层区域的较大孔则被空气填充。通过全矢量有限时域（FDTD）方法研究了所设计的PCF结构的光学特性，包括色散，有效模面积，限制损耗，归一化频率和非线性系数。以硅酸铅为晶片的PCF结构比以二氧化硅为晶片的PCF结构表现出明显更好的结果。然而，两个结构均报告了在对应于1.55μm的电信波长处的色散。此外，以硅酸铅为晶片的PCF结构表现出非常高的非线性系数，相当于1375 W^-1  km ^-1在相同波长下。通过利用非线性原理，该方案可用于光通信系统和光学设备。