基于液体填充的聚合物光纤偏振分束器设计

Design of liquid-filled polarization beam splitter of polymer fiber

偏振分束器是集成光子学、光纤通信和光纤传感等领域中非常重要的基本器件。利用矢量光束传播法优化设计了一种新型液体填充的聚合物光子晶体光纤偏振分束器,并对偏振分束器的耦合长度、耦合长度比率、消光比、带宽和双折射等特性进行了数值计算。结果表明,通过液体填充聚合物光子晶体光纤,获得了高双折射、短耦合长度、宽工作带宽的偏振分束器。该偏振分束器具有1.74×10^3的高双折射,高的双折射可以促进x-偏振与y-偏振模的耦合,有效地减小两种偏振态的耦合长度。当周期∧=0.9相对孔间隔比为d/∧=0.9,液体填充孔径为d1=0.34μm时,该偏振分束器的长度为746μm,低于-10dB的消光比带宽为70.2nm.

The polarization beam splitter is an essential component in varieties of fields, such as integrated photonics, optical fiber communications, and optical fiber sensing. This paper presents a new polarization beam splitter based on liquid-filled polymer photonic crystal fiber by using a vector beam propagation method, and its coupling length, coupling length ratio, extinction ratio, bandwidth, and birefringence are calculated numerically. The results indicate that the polarization beam splitter with high birefringence, short coupling length, and wide bandwidth is obtained via liquid-filled photonic crystal fiber. The polarization beam splitter has a high birefringence of 1. 74 ×10^-3, which can promote the coupling of x- and y-polarization modes and effectively reduce the coupling length of the two polarization states. When ∧=0. 9 μm, d/∧=0. 9, and d1=0.34μm, the polarization beam splitter offers a short length of 746 pm, and an extinction ratio higher than -10 dB has achieved a bandwidth of 70. 2 nm.