Attosecond-pump attosecond-probe x-ray spectroscopy of liquid water

• 成果类型: Article
• 署名作者: Li, Shuai; Lu, Lixin; Bhattacharyya, Swarnendu; Pearce, Carolyn; Li, Kai; Nienhuis, Emily T.; Doumy, Gilles; Schaller, R. D.; Moeller, S.; Lin, M. -F.; Dakovski, G.; Hoffman, D. J.; Garratt, D.; Larsen, Kirk A.; Koralek, J. D.; Hampton, C. Y.; Cesar, D.; Duris, Joseph; Zhang, Z.; Sudar, Nicholas; Cryan, James P.; Marinelli, A.; Li, Xiaosong; Inhester, Ludger; Santra, Robin; Young, Linda
• 署名单位: United States Department of Energy (DOE); Argonne National Laboratory; University of Washington; University of Washington Seattle; Helmholtz Association; Deutsches Elektronen-Synchrotron (DESY); United States Department of Energy (DOE); Pacific Northwest National Laboratory; Washington State University; University of Chicago; University of Chicago; United States Department of Energy (DOE); Argonne National Laboratory; Stanford University; United States Department of Energy (DOE); SLAC National Accelerator Laboratory; Stanford University; United States Department of Energy (DOE); SLAC National Accelerator Laboratory; University of Hamburg; University of Hamburg
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-10215
• DOI: 10.1126/science.adn6059
• 发表日期: 2024-03-08
• 页码: 1118-1122
• 关键词: dynamics; pulses; TRANSITION; phase; time

摘要

Attosecond-pump/attosecond-probe experiments have long been sought as the most straightforward method for observing electron dynamics in real time. Although there has been much success 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 through 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 of two structural motifs in ambient liquid water.