Author(s): Zhang, ZY (Zhang, Zanyun); Chen, X (Chen, Xia); Cheng, Q (Cheng, Qian); Khokhar, AZ (Khokhar, Ali Z.); Zhang, Z (Zhang, Zan); Yan, XZ (Yan, Xingzhao); Huang, BJ (Huang, Beiju); Chen, HD (Chen, Hongda); Liu, HW (Liu, Hongwei); Li, HQ (Li, Hongqiang); Thomson, DJ (Thomson, David J.); Reed, GT (Reed, Graham T.)

Source: JOURNAL OF LIGHTWAVE TECHNOLOGY Volume: 38 Issue: 15 Pages: 4037-4044 DOI: 10.1109/JLT.2020.2986043 Published: AUG 1 2020

Abstract: A four-port grating coupler with etched square holes is proposed and demonstrated for surface-normal and polarization independent coupling. Benefiting from the perfectly vertical coupling and 1x4 power splitting/combing scheme, efficient polarization independent operation was achieved. The coupling efficiency was further improved by grating apodization. According to the simulations, the proposed 2D apodized grating coupler can achieve a coupling efficiency (CE) of 64.5% (-1.9 dB), a low upward back-reflection of 8.5% (-11 dB), and polarization-dependent loss (PDL) lower than 0.04 dB across the wave length range of 1520-1620 nm. A CE of 56.3% (-2.5 dB) was experimentally measured, with PDL below 0.3 dB within the C-band and lower than 0.5 dB within the L-band. Waveguide delay lines were used to compensate the waveguide channel phase differences at the output port.

Accession Number: WOS:000565829100027

Author Identifiers:

Author        Web of Science ResearcherID        ORCID Number

Chen, Xia         B-8189-2011         0000-0002-0994-5401

ISSN: 0733-8724

eISSN: 1558-2213

Full Text: https://ieeexplore.ieee.org/document/9060954