设计了一种聚甲基丙烯酸甲酯(PMMA)基的单偏振单模(SPSM)微结构聚合物光纤(MPOF)。采用全矢量平面波展开法并结合完美匹配边界条件,对其偏振特性进行了理论模拟。详细讨论了微结构光纤参数的变化对单偏振单模带宽和工作波长的影响,发现在0.57～0.71 μm的可见光波长范围,由于基模两个正交偏振模的截止波长不同,这种微结构聚合物光纤只能传输基模中的一个偏振模。光束传播法计算表明,在波长0.65 μm处具有7圈空气孔的单偏振单模微结构聚合物光纤的传导偏振模约束损耗仅为1.24 dB/m,这种低损耗的单偏振单模微结构聚合物光纤可有效消除传统保偏光纤固有的偏振串扰和偏振模色散。

The single-polarization single-mode (SPSM) micro-structured polymer optical fiber (MPOF) was designed based on polymethyl methacrylate (PMMA). A full vector plane wave expansion method together with perfectly matched boundary conditions is adopted to study the SPSM properties. The dependence of SPSM bandwidth and operation wavelength on fiber parameters was investigated numerically. It indicates that only one polarization state of the fundamental mode can be transmitted within the visible light region from 0.57 μm to 0.71 μm according to the different cutoff wavelength for two orthogonal polarization modes. Moreover, the confinement loss of guiding mode is investigated using the beam propagation method. For MPOF with only 7 rings of holes, the confinement loss less than 1.24 dB/m is obtained at the 0.65 μm. This low loss SPSM-MPOF can greatly eliminate the polarization crosstalk and polarization mode dispersion.