Xiong Bo, Ma Wei, Wang Weiping, Hu Xiaoyan, Chu Tao
Opt Express. 2022 Sep 26;30(20):36254-36264. doi: 10.1364/OE.467418.
We proposed a new type of vertical grating couplers (VGCs) with a compact footprint on the 220-nm silicon-on-insulator platform. The overall size of the device containing the L-shaped coupling grating and the taper with achromatic in-plane metalens is only 45 × 15 µm, and the measured coupling efficiency at 1550 nm is -5.2 dB with a 1 dB bandwidth of 38 nm, around 1.6 dB higher than the VGC without metalens. The incidence angle mismatch has a 1 dB bandwidth of roughly 4°, whereas the displacement mismatch along the x-/y- axis has a bandwidth of around 3/4 µm. Furthermore, we experimentally show that such a design is compatible with VGCs operating in the S, C, and L bands.
我们在220纳米绝缘体上硅平台上提出了一种新型的垂直光栅耦合器（VGC），其占用面积紧凑。包含L形耦合光栅和具有消色差面内超透镜的锥形结构的器件整体尺寸仅为45×15 µm，在1550 nm处测得的耦合效率为-5.2 dB，1 dB带宽为38 nm，比没有超透镜的VGC高出约1.6 dB。入射角失配的1 dB带宽约为4°，而沿x/y轴的位移失配带宽约为3/4 µm。此外，我们通过实验表明，这种设计与在S、C和L波段工作的VGC兼容。
