Photonics Research Group Home
Ghent University Journals/Proceedings
About People Research Publications Education Services


Publication detail

Authors: Y. Zhu, J. Wang, W. Xie, B. Tian, Y. Li, E. Brainis, Yuqing Jiao, D. Van Thourhout
Title: Ultra-Compact Silicon Nitride Grating Coupler for Microscopy Systems
Format: International Journal
Publication date: 12/2017
Journal/Conference/Book: Optics Express
Volume(Issue): 25(26) p.33297-33304
DOI: 10.1364/oe.25.033297
Citations: 17 ( - last update: 26/5/2024)
4 (OpenCitations - last update: 19/4/2024)
Look up on Google Scholar
Download: Download this Publication (2.4MB) (2.4MB)


Grating couplers have been widely used for coupling light between photonic chips
and optical fibers. For various quantum-optics and bio-optics experiments, on the other hand,
there is a need to achieve good light coupling between photonic chips and microscopy
systems. Here, we propose an ultra-compact silicon nitride (SiN) grating coupler optimized
for coupling light from a waveguide to a microscopy system. The grating coupler is about 4
by 2 ¦Ìm2 in size and a 116 nm 1 dB bandwidth can be achieved theoretically. An optimized
fabrication process was developed to realize suspended SiN waveguides integrated with these
couplers on top of a highly reflective bottom mirror. Experimental results show that up to 53%
(2.76 dB loss) of the power of the TE mode can be coupled from a suspended SiN waveguide
to a microscopy system with a numerical aperture (NA) 0.65. Simulations show this
efficiency can increase up to 75% (1.25 dB loss) for NA = 0.95.

Related Research Topics

Back to publication list