Open AccessUnidirectional large-scale waveguide grating with uniform radiation for optical phased array
Author(s) -
Baisong Chen,
Yingzhi Li,
Lanxuan Zhang,
Yuxuan Li,
Xiaobin Liu,
Min Tao,
Yu Hou,
Hongxiao Tang,
Zihao Zhi,
Fengli Gao,
Xianshu Luo,
GuoQiang Lo,
Jun-Feng Song
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.427999
Subject(s) - optics , grating , waveguide , radiation , materials science , apodization , phased array optics , phased array , optoelectronics , physics , telecommunications , computer science , antenna (radio)
Two novel waveguide gratings for optical phased array transmitters are investigated. By offsetting the grating structures along the waveguide on the upper and lower surfaces of the silicon nitride (Si 3 N 4 ) waveguide, the dual-level chain and dual-level fishbone structures can achieve 95% of unidirectional radiation with a single Si 3 N 4 layer by design. With apodized perturbation along the gratings, both structures can achieve uniform radiation without compromising the unidirectional radiation performance. In experiment, both demonstrate ∼ 80-90% unidirectionality. With further analysis, it is found that the dual-level fishbone structure is more feasible and robust to process variations in uniform radiation.