设计了一种新型结构的宽带低损耗光子晶体光纤, 在其内包层引入6个大空气孔和6个椭圆空气孔, 并用全矢量有限元法研究了该光纤的模场分布、工作带宽、限制损耗和色散特性。数值计算结果表明, 该光纤在1.40~1.73 μm波段实现了低损耗SMSP(单模单偏振)特性, 只有y偏振模存在, 限制损耗小于0.1 dB/km, 色散平坦度为3.3 ps/(km·nm)。研究结果对设计新型高性能SMSP光纤具有一定的指导意义。

A novel structured low-loss broadband Photonic Crystal Fiber (PCF) is proposed, in the inner cladding of which six large air holes and six elliptical air holes are arranged. The fiber properties, such as mode field distribution, working bandwidth, confinement loss and dispersion, are analyzed by using the full-vector Finite Element Method (FEM). The numerical computation results show that this fiber demonstrates the features of low-loss Single-Mode and Single-Polarization (SMSP) at 1.40~1.73 μm waveband only when the y -polarization mode exists, the confinement loss is less than 0.1 dB/km and the dispersion flatness is 3.3 ps/(km·nm). The research results have certain instructive significance to the design of novel high performance SMSP-PCF.