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Photonic chip-based low noise microwave oscillator



Igor Kudelin, William Groman, Scott Diddams, Dahyeon Lee, Megan Kelleher, Takuma Nakamura, Charles McLemore, Franklyn Quinlan, Qing-Xin Ji, Joel Guo, Andrey Matsko, John Bowers, Kerry Vahala, Warren Jin, Lue Wu, Yifan Liu, Wei Zhang, Steven Bowers, Joe Campbell, Pedram Shirmohammadi, Samin Hanifi, Haotian Cheng, Naijun Jin, Sam Halliday, Zhaowei Dai, Chao Xiang, Vladimir Iltchenko, Owen Miller, Peter Rakich


Numerous modern technologies are reliant on the low-phase noise and timing stability performance of microwave signals. Substantial progress has been made in the field of microwave photonics, whereby low noise microwave signals are generated by the down-conversion of ultra-stable optical references using a frequency comb. Such systems, however, are constructed with bulk or fiber optics and are difficult to further reduce in size and power consumption. In this work, we leverage advances in integrated photonics to demonstrate low-noise microwave generation via two-point optical frequency division. Narrow linewidth self-injection locked integrated lasers are stabilized to a miniature Fabry-P\'e}rot cavity, and the frequency gap between the lasers is divided with an efficient dark-soliton frequency comb. The stabilized output of the microcomb is photodetected to produce a microwave signal at 20 GHz with phase noise of -95 dBc/Hz (-136.8 dBc/Hz) at 100 Hz (10 kHz) offset frequency--values which are unprecedented for an integrated photonic system. All photonic components can be heterogeneously integrated on a single chip, providing a significant advance for the application of photonics to high-precision navigation, communication and timing systems.
Nature Photonics


Microwave Photonics, Integrated Photonics, Phase Noise


Kudelin, I. , Groman, W. , Diddams, S. , Lee, D. , Kelleher, M. , Nakamura, T. , McLemore, C. , Quinlan, F. , Ji, Q. , Guo, J. , Matsko, A. , Bowers, J. , Vahala, K. , Jin, W. , Wu, L. , Liu, Y. , Zhang, W. , Bowers, S. , Campbell, J. , Shirmohammadi, P. , Hanifi, S. , Cheng, H. , Jin, N. , Halliday, S. , Dai, Z. , Xiang, C. , Iltchenko, V. , Miller, O. and Rakich, P. (2024), Photonic chip-based low noise microwave oscillator, Nature Photonics, [online],, (Accessed June 25, 2024)


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Created March 6, 2024, Updated June 7, 2024