Waveguide grating couplers with bandwidth beyond 200 nm

We propose and validate a new approach for wideband waveguide grating couplers (GC). The wideband operation is achieved using a slot waveguide grating structure above the conventional channel waveguide. With this slot waveguide grating structure, both the grating strength, mode effective index and d...

Full description

Saved in:
Bibliographic Details
Main Authors: Zhou Xuetong, Xue Ying, Feng Hanke, He Jianfeng, Sun Xiankai, Wang Cheng, Lau Kei May, Tsang Hon Ki
Format: Article
Language:English
Published: De Gruyter 2025-03-01
Series:Nanophotonics
Subjects:
Online Access:https://doi.org/10.1515/nanoph-2024-0683
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850060921524715520
author Zhou Xuetong
Xue Ying
Feng Hanke
He Jianfeng
Sun Xiankai
Wang Cheng
Lau Kei May
Tsang Hon Ki
author_facet Zhou Xuetong
Xue Ying
Feng Hanke
He Jianfeng
Sun Xiankai
Wang Cheng
Lau Kei May
Tsang Hon Ki
author_sort Zhou Xuetong
collection DOAJ
description We propose and validate a new approach for wideband waveguide grating couplers (GC). The wideband operation is achieved using a slot waveguide grating structure above the conventional channel waveguide. With this slot waveguide grating structure, both the grating strength, mode effective index and dispersion in the grating region can be flexibly tuned to enable high coupling efficiency and wideband operation. 3D FDTD simulations predicted coupling efficiency of −4.08 dB with unprecedented 1 dB bandwidth of 229 nm. The experimental result in coupling with standard single mode fiber in the C band to a lithium niobate waveguide achieved −4.47 dB coupling efficiency with 1 dB bandwidth of 171 nm and 3 dB bandwidth of over 200 nm. The unprecedented wide optical bandwidth is achieved without using bottom metal reflectors or the etching of grating structures on the lithium niobate material.
format Article
id doaj-art-941de535cece4380b35a1a18dc508da5
institution DOAJ
issn 2192-8614
language English
publishDate 2025-03-01
publisher De Gruyter
record_format Article
series Nanophotonics
spelling doaj-art-941de535cece4380b35a1a18dc508da52025-08-20T02:50:26ZengDe GruyterNanophotonics2192-86142025-03-0114557157910.1515/nanoph-2024-0683Waveguide grating couplers with bandwidth beyond 200 nmZhou Xuetong0Xue Ying1Feng Hanke2He Jianfeng3Sun Xiankai4Wang Cheng5Lau Kei May6Tsang Hon Ki7Department of Electronic Engineering, 105827The Chinese University of Hong Kong, Shatin, Hong Kong, ChinaDepartment of Electronic and Computer Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, ChinaDepartment of Electrical Engineering & State Key Laboratory of Terahertz and Millimeter Waves, City University of Hong Kong, Kowloon, ChinaDepartment of Electronic Engineering, 105827The Chinese University of Hong Kong, Shatin, Hong Kong, ChinaDepartment of Electronic Engineering, 105827The Chinese University of Hong Kong, Shatin, Hong Kong, ChinaDepartment of Electrical Engineering & State Key Laboratory of Terahertz and Millimeter Waves, City University of Hong Kong, Kowloon, ChinaDepartment of Electronic and Computer Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, ChinaDepartment of Electronic Engineering, 105827The Chinese University of Hong Kong, Shatin, Hong Kong, ChinaWe propose and validate a new approach for wideband waveguide grating couplers (GC). The wideband operation is achieved using a slot waveguide grating structure above the conventional channel waveguide. With this slot waveguide grating structure, both the grating strength, mode effective index and dispersion in the grating region can be flexibly tuned to enable high coupling efficiency and wideband operation. 3D FDTD simulations predicted coupling efficiency of −4.08 dB with unprecedented 1 dB bandwidth of 229 nm. The experimental result in coupling with standard single mode fiber in the C band to a lithium niobate waveguide achieved −4.47 dB coupling efficiency with 1 dB bandwidth of 171 nm and 3 dB bandwidth of over 200 nm. The unprecedented wide optical bandwidth is achieved without using bottom metal reflectors or the etching of grating structures on the lithium niobate material.https://doi.org/10.1515/nanoph-2024-0683integrated opticsphotonic integrated circuitgrating couplerssilicon photonicssilicon on insulator technology
spellingShingle Zhou Xuetong
Xue Ying
Feng Hanke
He Jianfeng
Sun Xiankai
Wang Cheng
Lau Kei May
Tsang Hon Ki
Waveguide grating couplers with bandwidth beyond 200 nm
Nanophotonics
integrated optics
photonic integrated circuit
grating couplers
silicon photonics
silicon on insulator technology
title Waveguide grating couplers with bandwidth beyond 200 nm
title_full Waveguide grating couplers with bandwidth beyond 200 nm
title_fullStr Waveguide grating couplers with bandwidth beyond 200 nm
title_full_unstemmed Waveguide grating couplers with bandwidth beyond 200 nm
title_short Waveguide grating couplers with bandwidth beyond 200 nm
title_sort waveguide grating couplers with bandwidth beyond 200 nm
topic integrated optics
photonic integrated circuit
grating couplers
silicon photonics
silicon on insulator technology
url https://doi.org/10.1515/nanoph-2024-0683
work_keys_str_mv AT zhouxuetong waveguidegratingcouplerswithbandwidthbeyond200nm
AT xueying waveguidegratingcouplerswithbandwidthbeyond200nm
AT fenghanke waveguidegratingcouplerswithbandwidthbeyond200nm
AT hejianfeng waveguidegratingcouplerswithbandwidthbeyond200nm
AT sunxiankai waveguidegratingcouplerswithbandwidthbeyond200nm
AT wangcheng waveguidegratingcouplerswithbandwidthbeyond200nm
AT laukeimay waveguidegratingcouplerswithbandwidthbeyond200nm
AT tsanghonki waveguidegratingcouplerswithbandwidthbeyond200nm