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arXiv · 1906.12027

Ultra-Compact Coupling Structures for Heterogeneously Integrated Silicon Lasers

An He·Lu Sun·Hongwei Wang·Xuhan Guo·Yikai Su
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Abstract

Due to the inherent in-direct bandgap nature of Silicon, heterogeneous integration of semiconductor lasers on Silicon on Insulator (SOI) is crucial for next-generation on-chip optical interconnects. Compact, high-efficient and high-tolerant couplers between III-V light source and silicon chips have been the challenge for photonic integrated circuit (PIC). Here, we redesign the taper adiabatic coupler with the total coupling length of only 4 {\mu}m, and propose another two novel slot coupler and bridge-SWG coupler with both coupling length of 7 {\mu}m, to heterogeneously integrate III-V lasers and silicon chips. We study theoretically the optical mode coupling process through the redesigned taper coupler, the final coupling results match well with the simulation in 3D-FDTD. The three compact couplers represent fundamental TE mode coupling efficiencies all over 90%, even 95.7% for bridge-SWG coupler, to the best of our knowledge, are also the shortest coupling structures (7 um). Moreover, these coupling structures also possess excellent fabrication tolerance.

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An He, Lu Sun, Hongwei Wang, Xuhan Guo, Yikai Su. 2019-06-28. Ultra-Compact Coupling Structures for Heterogeneously Integrated Silicon Lasers. https://arxiv.org/abs/1906.12027

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