熔锥型保偏光纤耦合器耦合系数分析

Coupling Coefficient Analysis of Fused Polarization-maintaining Fiber Couplers

耦合系数会直接影响到偏振光经过耦合器熔锥区后的光能量分布,从而影响保偏光纤耦合器的耦合性能。基于光波导模式耦合理论,建立了熔锥型保偏光纤耦合器的耦合模型,推导出了适应于纤芯为圆型、偏振主轴非平行时保偏光纤耦合器的耦合系数计算公式,形式简单、应用方便。为耦合模方程的求解以及耦合器的性能分析提供了前提条件,从而为熔锥型保偏光纤耦合器的高性能制造提供了理论指导。

Coupling coefficient will directly influence the light distribution of linearly polarized light through the Fused-Tapered zone of Polarization Maintaining Fiber（PMF） couplers. Accordingly, it affects the coupling performance of the couplers. Coupling model of fused polarization-maintaining fiber couplers is built on the basis of coupling mode theory of optical waveguide. A new formula for coupling coefficient of PMF couplers has been derived. It is appropriate for any PMF when the core is circ^ar and the bireffingent axes are nonaligned. The conclusion of the research can provide the precondition to solve the coupled mode equation and analyze the performance of couplers. Therefore, theoretical direction for the high-performance manufacturing of PMF couplers is provided.