零双折射温度敏感系数保偏光子晶体光纤研究

Study of Polarization-Maintaining Photonic Crystal Fibers with Zero Birefringent Temperature Sensitive Coefficient

分析了影响保偏光子晶体光纤(PM-PCF)双折射温度敏感性的因素,利用有限元法仿真研究了热光效应和热膨胀效应对典型的实心结构PM-PCF双折射温度敏感系数的影响。结果表明在-150℃^+150℃的工作温度范围内,热光效应对双折射的影响可以忽略。得到了这种PM-PCF双折射温度敏感系数与相邻空气小孔圆心距离Λ的多项式模型,在Λ=5.24μm时,双折射的温度敏感系数为零。制作了5根不同Λ的PM-PCF样品,采用基于混合Sagnac干涉仪的测量技术分别测试了样品光纤双折射值随温度的变化,在Λ=5.16μm时,双折射的温度敏感系数为零,与仿真结果吻合。

The factors that affect the temperature sensitivity of typical polarization-maintaining photonic crystal fibers （PM-PCF） are analyzed. By using the finite elements method, the influence of temperature on the birefringence of the typical solid core PM-PCF is studied, which mainly includes thermo-optic effects and thermal expansion. The results show that the thermo-optic effects can be neglected and the temperature sensitivity of birefringence can be represented only by a polynomial function of the center distance of adjacent air holes A under the working temperature from - 150 ℃to 150℃. The birefringence increases with A and becomes zero at A =5.16 μm. The compact hybrid Sagnac interferometer is used to measure the birefringence of five PM-PCF samples with different A under different temperatures. The experimental results conform well to the simulation.