双芯光子晶体光纤的带隙及色散特性

Band gap and dispersion property of dual-core photonic crystal fibers

为了研究双芯光子晶体光纤的带隙和色散特性,采用平面波展开法计算了双芯光子晶体光纤的带隙特性,当相对孔径 d/A≥0.2时,归一化传播常数βA的增大,导致光子禁带宽度增加,利用空气导光的工作波长范围越大。并采用全矢量模型分析了双芯 PCF 的色散特性,得到了通过适当调整光纤的结构参量,可以获得灵活的色散特性的结果。当孔距 A=2μm、相对孔径 d/A=0.4时,在波长1.55μm附近,获得近480nm 的超平坦色散区;随着相对孔径和孔距的增大,零色散点向短波长方向移动。这为制作高效传输光信号和高性能的保偏光纤提供了一个有效途径。

In order to study the photonic band gap and dispersion property of a dual-core photonic crystal fiber （PCF） ,the photonic band gap was calculated with the plane-wave expansion method. The calculation results show that when the relative aperture （d/∧） is larger than 0.2 ,the normalized propagation constant （β∧） increases,so the prohibited band and the range of wavelength propagating in the air-core increase. Secondly, the dispersion property of a dual-core was analyzed with a full vector model. The results show that the dispersion property can be adjusted with different structure parameters of fibers. Results show about 480nm of super flat dispersion area near 1.55 μm can be obtained with ∧ = 2μm, d/∧ = 0.4 ; with the relative aperture and aperture distance increasing, zero dispersion point will move to shorter-wave. The results of this study provide an effective way to produce efficient transmission optical fibers and high-performance polarization fibers.