2025-02-21 チャルマース工科大学
＜関連情報＞
- https://news.cision.com/chalmers/r/microcomb-chips-help-pave-the-way-for-thousand-times-more-accurate-gps-systems,c4108762
- https://www.nature.com/articles/s41566-025-01617-0
集積光学原子時計用バーニア・マイクロコーム Vernier microcombs for integrated optical atomic clocks
Kaiyi Wu,Nathan P. O’Malley,Saleha Fatema,Cong Wang,Marcello Girardi,Mohammed S. Alshaykh,Zhichao Ye,Daniel E. Leaird,Minghao Qi,Victor Torres-Company & Andrew M. Weiner
Nature Photonics Published:19 February 2025
DOI:https://doi.org/10.1038/s41566-025-01617-0
Abstract
Kerr microcombs have drawn substantial interest as mass-manufacturable, compact alternatives to bulk frequency combs. This could enable the deployment of many comb-reliant applications previously confined to laboratories. Particularly enticing is the prospect of microcombs performing optical frequency division in compact optical atomic clocks. Unfortunately, it is difficult to meet the self-referencing requirement of microcombs in these systems owing to the approximately terahertz repetition rates typically required for octave-spanning comb generation. In addition, it is challenging to spectrally engineer a microcomb system to align a comb mode with an atomic clock transition with a sufficient signal-to-noise ratio. Here we adopt a Vernier dual-microcomb scheme for optical frequency division of a stabilized ultranarrow-linewidth continuous-wave laser at 871 nm to an ~235 MHz output frequency. This scheme enables shifting an ultrahigh-frequency (~100 GHz) carrier-envelope offset beat down to frequencies where detection is possible and simultaneously placing a comb line close to the 871 nm laser—tuned so that, if frequency doubled, it would fall close to the clock transition in 171Yb+. Our dual-comb system can potentially combine with an integrated ion trap towards future chip-scale optical atomic clocks.
