Johnson Mack, Thompson Mark G, Sahin Döndü
Opt Express. 2020 Apr 27;28(9):12498-12507. doi: 10.1364/OE.381304.
A waveguide crossing based on multi-mode interference is designed and experimentally characterized on the silicon platform. The insertion loss of the device is measured as 43 ± 4 mdB per crossing, with a crosstalk of < -50 dB between 1550 and 1560 nm, in good agreement with predictions from 3D finite-difference time-domain simulations. Furthermore, the device backscatter was investigated using white light reflectometry and no significant backscatter was observed from 160 waveguide crossings in the time domain. In the frequency domain, the backscatter of the waveguide crossing device was measured experimentally for the first time, achieving a backscatter of -55 dB. The crossing has a footprint of 14.3 x 14.3 µm and can be fabricated in a single step.
基于多模干涉的波导交叉结构在硅平台上被设计并进行了实验表征。该器件的插入损耗经测量为每个交叉点43±4 mdB，在1550至1560 nm之间的串扰小于-50 dB，与三维时域有限差分模拟的预测结果吻合良好。此外，利用白光反射法对器件的背向散射进行了研究，在时域中从160个波导交叉点未观察到明显的背向散射。在频域中，首次对波导交叉器件的背向散射进行了实验测量，实现了-55 dB的背向散射。该交叉结构的占地面积为14.3×14.3 µm，并且可以一步制造完成。
