Real-time observation of electronic, vibrational, and rotational dynamics in nitric oxide with attosecond soft X-ray pulses at 400 eV

Nariyuki Saito; Hiroki Sannohe; Nobuhisa Ishii; Teruto Kanai; Nobuhiro Kosugi; Yi Wu; Andrew Chew; Seunghwoi Han; Zenghu Chang; Jiro Itatani

arXiv · 1904.10456

Real-time observation of electronic, vibrational, and rotational dynamics in nitric oxide with attosecond soft X-ray pulses at 400 eV

Nariyuki Saito·Hiroki Sannohe·Nobuhisa Ishii·Teruto Kanai·Nobuhiro Kosugi·Yi Wu·Andrew Chew·Seunghwoi Han·Zenghu Chang·Jiro Itatani

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Abstract

Photoinduced quantum dynamics in molecules have hierarchical temporal structures with different energy scales that are associated with electron and nuclear motions. Femtosecond-to-attosecond transient absorption spectroscopy (TAS) using high-harmonic generation (HHG) with a photon energy below 300 eV has been a powerful tool to observe such electron and nuclear dynamics in a table-top manner. However, comprehensive measurements of the electronic, vibrational, and rotational molecular dynamics have not yet been achieved. Here, we demonstrate HHG-based TAS at the nitrogen K-edge (400 eV) for the first time, and observe all the electronic, vibrational, and rotational degrees of freedom in a nitric oxide molecule at attosecond to sub-picosecond time scales. This method of employing core-to-valence transitions offers an all-optical approach to reveal complete molecular dynamics in photochemical reactions with element and electronic state specificity.

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Nariyuki Saito, Hiroki Sannohe, Nobuhisa Ishii, Teruto Kanai, Nobuhiro Kosugi, Yi Wu, Andrew Chew, Seunghwoi Han, Zenghu Chang, Jiro Itatani. 2019-04-23. Real-time observation of electronic, vibrational, and rotational dynamics in nitric oxide with attosecond soft X-ray pulses at 400 eV. https://arxiv.org/abs/1904.10456

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