実験物理学の新分野を切り開く発見 Findings open a whole new field of experimental physics
2024-02-15 アルゴンヌ国立研究所(ANL)
Artistic rendering of attosecond X-ray pulses freezing all nuclear motion in liquid water, including those of the lightest hydrogen atoms. This allows researchers to isolate structural properties indicative of ambient water in its ground electronic state. (Image by Stacy Huang.)
＜関連情報＞
- https://www.anl.gov/article/firstever-atomic-freezeframe-of-liquid-water
- https://www.science.org/doi/10.1126/science.adn6059
液体水のアト秒ポンプ・アト秒プローブX線分光法 Attosecond-pump attosecond-probe x-ray spectroscopy of liquid water
SHUAI LI , LIXIN LU , SWARNENDU BHATTACHARYYA , CAROLYN PEARCE , […], AND LINDA YOUNG
Science Published:15 Feb 2024
DOI:https://doi.org/10.1126/science.adn6059
Abstract
Attosecond-pump/attosecond-probe experiments have long been sought as the most straightforward method to observe electron dynamics in real time. Although numerous successes have been achieved with overlapped near infrared femtosecond and extreme ultraviolet attosecond pulses combined with theory, true attosecond-pump/attosecond-probe experiments have been limited. We used a synchronized attosecond x-ray pulse pair from an x-ray free electron laser to study the electronic response to valence ionization in liquid water via all x-ray attosecond transient absorption spectroscopy (AX-ATAS). Our analysis showed that the AX-ATAS response is confined to the subfemtosecond timescale, eliminating any hydrogen atom motion and demonstrating experimentally that the 1b1 splitting in the x-ray emission spectrum is related to dynamics and is not evidence for two structural motifs in ambient liquid water.
