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Title: Broadband 2 × 2 multimode-interference coupler on the silicon-nitride platform
In this paper, we present the design, optimization, and implementation of a sub-wavelength grating (SWG) multi-mode interference coupler (MMI) on the silicon nitride photonic integrated circuit (PIC) platform with a significantly enhanced bandwidth compared to the conventional MMI. We extend the SWG MMI theory, previously presented for the silicon-on-insulator platform, to the Si3N4/SiO2platform. Our approach involves an initial parameter optimization for a non-paired design, followed by a shift to a paired design that offers a smaller footprint and a broader bandwidth. The optimized SWG MMI exhibits a 1 dB bandwidth of 300 nm for both the insertion loss and power imbalance, making it a significant addition to silicon nitride photonics.  more » « less
Award ID(s):
2219760
PAR ID:
10541596
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Optica
Date Published:
Journal Name:
Optics Express
Volume:
32
Issue:
6
ISSN:
1094-4087
Page Range / eLocation ID:
9405
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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