具有下陷纤芯与沟槽辅助包层结构的少模光纤

Few-mode Fiber with Depressed Core and Trench Assisted Cladding

为了降低模间串扰,提高抗弯曲性能,提出了一种具有下陷纤芯与沟槽辅助包层结构的少模光纤。该光纤在1.36~1.56μm波长范围内可支持7个LP模式的传输。包层中沟槽的引入使得各阶模式弯曲损耗在弯曲半径1cm时均小于1×10^(-7)dB/m,模式间有效折射率差均高于10^(-3)。基于有限元法分析了下陷纤芯和沟槽的结构参数对模式有效折射率和模场面积和弯曲特性的影响,重点分析了包层沟槽对弯曲性能的改善作用。研究表明,沟槽有利于降低高阶模式的弯曲损耗。

In order to reduce crosstalk and improve bend resistant performance,a few mode fiber with a depressed core and trench assisted cladding is proposed.The few mode fiber can support 7 LP modes within the wave length range of 1.36~1.56μm.The introduction of trench in the cladding makes the bending loss less than 1x10^(-7) dB/mata bending radius of 1 cm,the effective refractive index difference between each modes is higher than 10^(-3).Based on the finite element method,the influences of structural parameters such as depressed core,trench on the effective refractive index,mode field area,and bending performance are analyzed.Numerical analysis results show that the introduction of trench is beneficial for reducing bending losses of higher-order modes.