运用平面波展开法分析As2S3、Ge20Se65Sb15和As2Se3硫系玻璃光纤在不同空气填充率下的带隙分布图, 分析结果表明三种材料在空气填充率提高到0.75时, 光子带隙与空气线均出现交汇模式, 且带隙宽度大, 纤芯空气孔中适宜进行激光传输.运用有限元法分析不同纤芯孔直径的Ge20Se65Sb15硫系玻璃空芯光子带隙光纤的基模限制损耗和有效模场面积, 结果表明纤芯直径9.2 μm时限制损耗最低, 模场面积较小.通过优化光纤的结构参量, 适合于4.3 μm波长处高功率中红外激光传输的空芯光子带隙光纤, 其限制损耗为0.00472 dB/m, 有效模场面积为58.046 μm2.

The band-gap maps of As2S3, Ge20Se65Sb15 and As2Se3 chalcogenide glass fibers at different air-fillings were analyzed by using the plane wave expansion method,. The results show that when increased to 0.75, the photonic band gap and air lines have appeared intersection mode, the band gap is wide, and an appropriate laser transmission mode in the core of fiber is formed. Under different fiber core diameter, using the finite element method, the fundamental mode confinement loss and effective mode area of homemade Ge20Se65Sb15chalcogenide glass hollow-core photonic crystal fiber were systematically studied. The results show that the confinement loss is the lowest and the effective mode-field area is very small when the core diameter is 9.2 μm. By optimizing the structural parameters of fiber, a hollow-core photonic crystal fiber with low confinement loss (0.00472 dB/m) and effective mode-field area (58.046 μm2) at 4.3 μm was obtained.