为了研究10nm级铝包覆光波导特征参量对其耦合情况的影响，理论模拟了不同金属层折射率和厚度、不同导波层折射率和厚度情况下的衰减全反射谱，分析了特征参量对耦合情况的影响。通过实验验证了金属层折射率和厚度对其耦合情况的影响，发现纳米级铝膜的复介电常数发生了很大的变化。结果表明，导波层厚度影响激发导模的数目，但对耦合深度影响不大；导波层折射率同时影响激发导模的数目和耦合深度；耦合层金属膜厚度不影响激发导模的模数，但对耦合深度的影响很大；对于相同的耦合层金属膜厚度，金属折射率不同，耦合情况大不相同。研究结果为基于双面金属包覆光波导的脉冲展宽器的制作和设计过程提供了参考。

In order to study the influence of parameters in 10nm-class aluminium-cladding optical waveguide, the attenuation total reflection spectrum was simulated theoretically with different thickness and refractive index of the cover and film, and the effect of characteristic parameters on the coupling was analyzed. Finally the experiments verified the influence of the thickness and refractive index of the metal layer on the coupling. At the same time, it was found that the refractive index of the nanometer-class aluminium film changed a lot. It is concluded that the number of the guided modes are affected by the thickness of the film, which is unrelated with the coupling depth; the refractive index of the film affects the number of the guided modes and the coupling depth; the number of the guided modes was unrelated with the thickness of the cover, which affects the coupling depth; for the same thickness of the cover, the coupling condition varies with the refractive index of the cover. The research opens the doors for the manufacture and the design of the pulse stretchers based on symmetrical metal-cladding optical waveguide.