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


Publication detail

Authors: X. Nie, N. Turk, Y. Li, Z. Liu, R. Baets
Title: High extinction ratio on-chip pump-rejection filter based on cascaded grating-assisted contra-directional couplers in silicon nitride rib waveguides
Format: International Journal
Publication date: 4/2019
Journal/Conference/Book: Optics Letters
Volume(Issue): 44(9) p.2310-2313
DOI: 10.1364/OL.44.002310
Citations: 32 ( - last update: 7/7/2024)
24 (OpenCitations - last update: 27/6/2024)
Look up on Google Scholar
Download: Download this Publication (1.8MB) (1.8MB)


We present an on-chip filter that is based on the grating-assisted contra-directional coupler (GACDC) implemented on a silicon nitride rib waveguide platform. This filter enjoys the benefit of an unlimited free spectral range (FSR) on the red side of the stop/passband. Unlike a Bragg reflector, the GACDC filter has the advantage of coupling the rejected light contra-directionally into a bus waveguide, instead of reflecting it back to the input. This property makes it an add/drop filter suitable for pump rejection and allows effective cascading to provide an even higher extinction ratio compared to the single-stage version. In this Letter, we experimentally demonstrate that a 16-stage cascaded GACDC filter can provide a stop band with a bandwidth smaller than 3 nm and an extinction ratio as high as 68.5 dB.

Citations (OpenCitations)

Back to publication list