Gao Sai, Wang Hongwei, Yi XIaogen, Qiu Ciyuan
Opt Express. 2021 Nov 8;29(23):38683-38690. doi: 10.1364/OE.440634.
In this work, an ultra-sharp multimode waveguide bend (MWB) based on gradient shallowly etched grooves is proposed and demonstrated. With a bending radius of only 5.6 μm, our shallowly-etched-groove multimode waveguide bend (SMWB) can enable low excess loss and low-crosstalk propagation with the four lowest-order TE mode-channels, simultaneously. In the simulation, the excess losses of the proposed 90°- SMWB for TE-TE are all below 0.46 dB and the inter-mode crosstalks are lower than -18 dB in 1500 nm-1600 nm. Furthermore, the measured results of the fabricated 90°- SMWB show that the excess losses for TE-TE are less than 1 dB and the inter-mode crosstalks are all below -14 dB in 1510 nm-1580 nm. Such a proposed device thus provides a promising solution for ultra-compact MWBs in multimode silicon photonics.
在这项工作中，提出并展示了一种基于梯度浅蚀刻槽的超尖锐多模波导弯曲（MWB）。我们的浅蚀刻槽多模波导弯曲（SMWB）弯曲半径仅为5.6μm，能够同时实现四个最低阶TE模式通道的低额外损耗和低串扰传播。在仿真中，所提出的90°-SMWB在1500nm-1600nm范围内，TE-TE的额外损耗均低于0.46dB，模式间串扰低于-18dB。此外，所制备的90°-SMWB的测量结果表明，在1510nm-1580nm范围内，TE-TE的额外损耗小于1dB，模式间串扰均低于-14dB。因此，这种所提出的器件为多模硅光子学中的超紧凑MWB提供了一种有前景的解决方案。
