State Key Laboratory on Advanced Optical Communication Systems and Networks, Peking University, Beijing, China.
Opt Lett. 2011 Mar 15;36(6):837-9. doi: 10.1364/OL.36.000837.
We describe a compact double-layer waveguide grating splitter that not only achieves efficient coupling between single mode fiber and a silicon-on-insulator optical waveguide but also realizes effective splitting. By appropriate choice of waveguide/grating parameters, including thicknesses, periods, height, and fill factor to optimize the mode matching, coupling efficiency is improved and the value of power difference of each output port is also significantly decreased. The maximum of power difference between four output ports is about 6.2%; however, the minimum value is only 0.6% or so. Moreover, the average power difference of four output ports is lower than 10% for TE polarization light over the 10 nm wavelength bandwidth centered at 1.54 μm. In addition, the splitter structure has the best tolerance for grating fabrication with deviations of grating depth 90 nm.
我们描述了一种紧凑的双层波导光栅分束器，它不仅实现了单模光纤和绝缘体上硅光波导之间的高效耦合，而且还实现了有效的分光。通过适当选择波导/光栅参数，包括厚度、周期、高度和填充因子以优化模式匹配，可以提高耦合效率，同时显著降低每个输出端口的功率差。四个输出端口之间的最大功率差约为 6.2%；然而，最小值仅为 0.6%左右。此外，对于中心波长为 1.54μm、带宽为 10nm 的 TE 偏振光，四个输出端口的平均功率差低于 10%。此外，分束器结构对光栅制造具有最佳的容差，光栅深度偏差为 90nm。
