2023-10-30 米国国立標準技術研究所(NIST)
◆この新技術により、高速プロセス（超音速推進など）の瞬時の中間段階を理解するための新たな可能性が生まれました。この技術は、研究分野や産業の幅広いアプリケーションに使用でき、研究者にとっても利用しやすくなりました。研究は科学研究局の支援を受けて行われました。
＜関連情報＞
- https://www.nist.gov/news-events/news/2023/10/new-frequency-comb-can-identify-molecules-20-nanosecond-snapshots
- https://www.nature.com/articles/s41566-023-01316-8
ナノ秒時間分解デュアルコーム吸収分光法 Nanosecond time-resolved dual-comb absorption spectroscopy
David A. Long,Matthew J. Cich,Carl Mathurin,Adam T. Heiniger,Garrett C. Mathews,Augustine Frymire & Gregory B. Rieker
Nature Photonics Published:30 October 2023
DOI:https://doi.org/10.1038/s41566-023-01316-8
Abstract
Frequency combs have revolutionized the field of optical spectroscopy, enabling researchers to probe molecular systems with a multitude of accurate and precise optical frequencies. Although there have been tremendous strides in direct frequency comb spectroscopy, these approaches have been unable to record high-resolution spectra on the nanosecond-timescale characteristic of many physiochemical processes. Here we demonstrate a new approach to achieve optical frequency comb generation in which a pair of electro-optic combs is produced in the near-infrared regime and subsequently transferred with high mutual coherence and efficiency into the mid-infrared regime within a single optical parametric oscillator. The high power, mutual coherence and agile repetition rates of these combs, as well as the large mid-infrared absorption of many molecular species, enable fully resolved spectral transitions to be recorded in timescales as short as 20 ns. We have applied this approach to study the rapid dynamics occurring within a supersonic pulsed jet; however, we note that this method is widely applicable to fields such as chemical and quantum physics, atmospheric chemistry, combustion science and biology.
