Ou Xiangpeng, Yang Yan, Tang Bo, Li Donghao, Sun Fujun, Zhang Peng, Liu Ruonan, Li Bin, Li Zhihua
Opt Express. 2021 Jun 7;29(12):19049-19057. doi: 10.1364/OE.427802.
Slot waveguide has attracted a lot of attention due to its ability to confine light in the low refractive index region, while strip waveguide acts as the basic component of guiding light due to its relatively low optical loss. In the multifunctional photonic integrated chips, it is critical to achieve the low loss transition between the strip waveguide and the slot waveguide. In this work, a silicon nitride strip-slot mode converter with high efficiency, large bandwidth, and large fabrication tolerance are proposed and demonstrated through the numerical investigation and experiments. The coupling efficiency of the mode converter is up to - 0.1 dB (97.7%), which enables the extremely low transition loss between the strip waveguide and the slot waveguide. Moreover, the fabrication process of silicon nitride photonic devices with high performance is introduced, which is fully compatible with the CMOS technology. Photonic devices based on silicon nitride with the characteristics of the low optical loss and the temperature insensitivity represent a new paradigm in realizing silicon-based photonic multifunctional chips.
槽波导因其能够在低折射率区域限制光而备受关注，而条形波导则由于其相对较低的光损耗而作为导光的基本组件。在多功能光子集成芯片中，实现条形波导和槽波导之间的低损耗过渡至关重要。在这项工作中，通过数值研究和实验，提出并演示了一种具有高效率、大带宽和大制造容差的氮化硅条形-槽模式转换器。模式转换器的耦合效率高达-0.1 dB（97.7%），这使得条形波导和槽波导之间的过渡损耗极低。此外，还介绍了高性能氮化硅光子器件的制造工艺，该工艺与CMOS技术完全兼容。基于氮化硅的具有低光损耗和温度不敏感特性的光子器件代表了实现硅基光子多功能芯片的一种新范例。
