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 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.
Cite
@article{arxiv.2403.02828,
title = {A chip-integrated comb-based microwave oscillator},
author = {Wei Sun and Zhiyang Chen and Linze Li and Chen Shen and Jinbao Long and Huamin Zheng and Luyu Yang and Qiushi Chen and Zhouze Zhang and Baoqi Shi and Shichang Li and Lan Gao and Yi-Han Luo and Baile Chen and Junqiu Liu},
journal= {arXiv preprint arXiv:2403.02828},
year = {2025}
}