A chip-integrated comb-based microwave oscillator
Abstract: Low-noise microwave oscillators are cornerstones for wireless communication, radar and clocks. Optical frequency combs have enabled photonic microwaves with unrivalled noise performance and bandwidth. Emerging interest is to generate microwaves using chip-based frequency combs, namely microcombs. Here, we demonstrate the first, fully integrated, microcomb-based, microwave oscillator chip. The chip, powered by a microelectronic circuit, leverages hybrid integration of a DFB laser, a nonlinear microresonator, and a high-speed photodetector. Each component represents the best of its own class, yet allows large-volume manufacturing with low cost in CMOS foundries. The hybrid chip outputs an ultralow-noise laser of 6.9 Hz linewidth, a microcomb of 10.7 GHz repetition rate, and a 10.7 GHz microwave of 6.3 mHz linewidth -- all three in one entity of 76 mm$2$ size.The microwave phase noise reaches -75/-105/-130 dBc/Hz at 1/10/100 kHz Fourier offset frequency. Our results can reinvigorate our information society for communication, sensing, timing and precision measurement.
- Ye, Z. et al. Foundry manufacturing of tight-confinement, dispersion-engineered, ultralow-loss silicon nitride photonic integrated circuits. Photon. Res. 11, 558–568 (2023). URL https://opg.optica.org/prj/abstract.cfm?URI=prj-11-4-558.
- Luo, Y.-H. et al. A wideband, high-resolution vector spectrum analyzer for integrated photonics. arXiv 2304.04295 (2023).
- Kondratiev, N. M. et al. Self-injection locking of a laser diode to a high-Q WGM microresonator. Optics Express 25, 28167–28178 (2017).
- Kondratiev, N. M. et al. Recent advances in laser self-injection locking to high-q microresonators. Frontiers of Physics 18, 21305 (2023). URL https://doi.org/10.1007/s11467-022-1245-3.
- Diode Lasers and Photonic Integrated Circuits. Wiley Series in Microwave and Optical Engineering (Wiley, 2012). URL https://books.google.ch/books?id=GBB1kOYONT4C.
- Coherent optical fiber communications, vol. 4 (Springer Science & Business Media, 1988).
- Narrow linewidth cw laser phase noise characterization methods for coherent transmission system applications. Journal of Lightwave Technology 26, 3048–3055 (2008). URL https://ieeexplore.ieee.org/document/4738475.
- Jin, W. et al. Hertz-linewidth semiconductor lasers using cmos-ready ultra-high-q microresonators. Nature Photonics 15, 346–353 (2021). URL https://doi.org/10.1038/s41566-021-00761-7.
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