Low-loss, compact, spot-size-converter based vertical couplers for photonic integrated circuits
Abstract
In recent years, the monolithic integration of new materials such as SiN, Ge and LiNbO3 on silicon (Si) has become important to the Si photonics community due to the possibility of combining the advantages of both material systems. However, efficient coupling between the two different layers is challenging. In this work, we present a spot size converter based on a two-tier taper structure to couple the optical mode adiabatically between Si and SiN. The fabricated devices show a coupling loss as low as 0.058 dB ± 0.01 dB per transition at 1525 nm. The low coupling loss between the Si to SiN, and vice versa, reveals that this interlayer transition occurs adiabatically for short taper lengths (<200 µm). The high refractive index contrast between the Si and SiN is overcome by matching the optical impedance. The proposed two-tier taper structure provides a new platform for optoelectronic integration and a route towards 3D photonic integrated circuits.
Citation
Singaravelu , P K J , Devarapu , G C R , Schulz , S A , Wilmart , Q , Malhouitre , S , Olivier , S & O'Faolain , L 2019 , ' Low-loss, compact, spot-size-converter based vertical couplers for photonic integrated circuits ' , Journal of Physics D : Applied Physics , vol. 52 , no. 21 , 214001 . https://doi.org/10.1088/1361-6463/ab07d5
Publication
Journal of Physics D : Applied Physics
Status
Peer reviewed
ISSN
0022-3727Type
Journal article
Rights
© 2019, IOP Publishing Ltd. This work has been made available online in accordance with the publisher's policies. This is the author created accepted version manuscript following peer review and as such may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1088/1361-6463/ab07d5
Description
Funding: (i) European Union Horizon H2020 Programme (H2020-ICT27-2015, COSMICC No. 688516). (ii) European Union Research Council (ERC) starting grant 337508.Collections
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