提出了一种新结构的高双折射光子晶体光纤, 通过引入掺氟实心圆的方式形成双折射, 而不采用大多数高双折射光子晶体光纤中引入不同孔径空气孔或椭圆空气孔的结构。应用全矢量平面波法对其基模场分布、模式截止以及各种结构参量对模式双折射特性的影响进行了详细的分析和讨论。结果表明, 该结构光子晶体光纤可以在较宽波长范围内产生10-3量级的模式双折射, 且通过调节孔径, 可以灵活地将双折射最高点调整到所需的波长上。另外, 该结构高双折射光子晶体光纤在拉制工艺、光纤强度以及光纤熔接等方面也具有一定的优势。

A new type of high-birefringence photonic crystal fiber is brought forward, and the method introducing circinal holes with different sizes or elliptical holes which is used to design high-birefringence photonic crystal fiber is replaced by introducing fluorine-doped solid circles. Then the characteristics of fundmental mode field distribution, mode cutoff, and the effect of all structure parameters on the birefringence are analyzed and discussed in detail by full-vector plane wave method. It is concluded that this type of photonic crystal fiber can offer birefringence higher than 10-3 in a rather broad wavelength range, and moreover, the peak of birefringence can be moved to the demanded wavelength by adjusting the hole spacing. Otherwise, it also has some advantages in the aspects of fiber drawing technique, fiber strength and fiber splicing.