The eigenmode expansion method is applied to discretize the stepped shine grating into a binary shine grating. Various strategies that increase the directionality of the coupling efficiency have been optimized and replicated using this binary shining grating. We discussed and analyzed the impact of distributed Bragg reflectors, slits, and metal reflectors on the coupling efficiency of grating couplers. A metal reflector and slit were included in the design of a binary shine grating coupler. The coupling efficiency from the fiber to the waveguide of vertically incident electrically polarized light is 75.07% at 1600 nm. A 3 dB bandwidth of 77 nm from 1554 to 1631 nm is obtained.

中文翻译：

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高效、完美垂直的带狭缝的二元闪耀光栅耦合器

采用本征模展开法将阶梯式闪耀光栅离散成二值闪耀光栅。使用这种二元发光光栅优化并复制了各种提高耦合效率方向性的策略。我们讨论并分析了分布式布拉格反射器、狭缝和金属反射器对光栅耦合器耦合效率的影响。二元闪耀光栅耦合器的设计中包括金属反射器和狭缝。垂直入射电偏振光从光纤到波导的耦合效率在 1600 nm 处为 75.07%。获得 1554 至 1631 nm 范围内 77 nm 的 3 dB 带宽。