圆芯边孔光纤模式场分布和双折射的研究

Research on the Distribution of Model Electric Field and Birefringence in Circular-core Side-hole Fibers

对圆芯边孔光纤双折射的研究结果进行报道。使用有限元方法建立了包括计算圆芯边孔光纤横截面应力分布、折射率分布和双折射的模型,计算了圆芯边孔光纤的模式场分布、几何双折射和应力致双折射。研究表明,圆芯边孔光纤的应力致双折射很小,这是圆芯边孔光纤自身的特殊结构造成的。比较了几种不同边孔形状的光纤的双折射,提出了圆芯边孔光纤的优化结构。

The intrinsic birefringence in drcular-core side-hole fiber is reported. The finite element method is used to build the model,in which the stress distribution and the refractive index distribution in the cross section of the fiber and the birefringence are calculated. The model electric field,the geometrical and stress-induced birefringence are calculated. It is concluded that in circular-core side hole fiber, the geometrical birefringence is dominant. The reason why the stress-induced birefrin gence is minute lies in the special structure of the fiber when the variation of the model electric field distribution and the limiting factor of the power are considered. The birefringence of some other drcular-core side-hole fibers which have different side-hole are also calculated in this paper,and an optimized structure design of the side-hole fiber is drawn.