High-performance, adiabatically nanotapered fibre-chip couplers in silicon at 2 microns wavelength
Citation
Sulway, D. A., Yonezu, Y., Rosenfeld, L. M., Jiang, P., Aoki, T., & Silverstone, J. W. (2022). High-performance, adiabatically nanotapered fibre-chip couplers in silicon at 2 microns wavelength. arXiv preprint arXiv:2209.08931.
Keywords
- Silicon photonics
- Fiber-chip coupling
- Adiabatic coupling
- Nanotapered fiber
- Silicon nanowire
- Mid-infrared (MIR)
- Low-loss
- Broadband
- Vertical grating coupler (VGC)
- Integrated optics
Brief
A new method is demonstrated for coupling light between optical fibers and silicon photonic chips that is low-loss, broadband, easily manufacturable, and naturally planar.
Summary
This article discusses a new method for connecting optical fibers to silicon photonic chips. The authors present a nanotapered fiber coupler (NTFC), which offers advantages over existing methods like vertical grating couplers and edge couplers. Here are the key aspects of the NTFC:
- Functionality: The NTFC adiabatically couples light between a tapered silicon nanowire waveguide on the chip and a conic nanotapered optical fiber.
- Performance: The NTFC demonstrates high efficiency (-0.48 dB transmission), a broad bandwidth (295 nm), and robustness to misalignment (±0.968 µm).
- Fabrication: The silicon chip is fabricated at a commercial foundry and then post-processed to create the suspended, tapering silicon nanowires.
- Advantages: This method is low-loss, broadband, easily manufacturable, and naturally planar. The authors suggest that the NTFC design could be applied to other materials, such as silicon nitride and lithium niobate, potentially enabling the creation of modular photonic systems with low-loss fiber interconnects between different materials