Attosecond spectroscopy reveals spontaneous symmetry breaking in molecular photoionization
Spontaneous symmetry breaking, driven by nonadiabatic electron-nuclear coupling, can lead to geometric complexity in molecules and solids. While structural distortion from symmetry breaking occurs in femtoseconds, the timescale to lift electronic state degeneracy has remained elusive. We use the vibrationally resolved attosecond chronoscope to capture the electronic symmetry breaking induced by the Renner-Teller effect in bent CO<sub>2</sub> molecules after photoionization by an extreme ultraviolet photon by measuring attosecond ionization delays. Relative photoionization delays between the four cation states are observed, with vibrational state-dependent delays, we analyze the evolution of the degenerate [Formula: see text] state to the nondegenerate <i>A</i>' and <i>A</i>″ states due to molecular bending. With the help of theoretical analysis, we show that the relative photoionization delays of up to 72 as between the vibrational levels originate from the symmetry breaking-induced shape resonance. This study offers fundamental insights by resolving the coupled electron and structural dynamics simultaneously.
Authors
- Sizuo Luo (ORCID: https://orcid.org/0000-0002-8969-5958)
- Leshi Zhao
- David Busto (ORCID: https://orcid.org/0000-0003-4311-3315)
- Jun Cai (ORCID: https://orcid.org/0000-0003-2369-1396)
- Mingxuan Li (ORCID: https://orcid.org/0000-0003-1186-3314)
- Robin Weissenbilder (ORCID: https://orcid.org/0000-0002-8081-3727)
- Wentao Wang (ORCID: https://orcid.org/0009-0002-7876-6375)
- Xiaoming Shi (ORCID: https://orcid.org/0000-0001-7332-6835)
- Kiyoshi Ueda (ORCID: https://orcid.org/0000-0001-8051-8966)
- Jialong Li (ORCID: https://orcid.org/0009-0007-9982-3611)
- Mathieu Gisselbrecht (ORCID: https://orcid.org/0000-0003-0257-7607)
- Dajun Ding (ORCID: https://orcid.org/0000-0003-3120-8392)
- Ming Zhang (ORCID: https://orcid.org/0000-0002-0329-1275)
- Zheng Li (ORCID: https://orcid.org/0000-0002-5483-9149)
- Xinning Zhao (ORCID: https://orcid.org/0000-0001-9666-962X)
- Xiaoyan Hong (ORCID: https://orcid.org/0000-0002-0745-5038)
- Huiyong Wang (ORCID: https://orcid.org/0000-0003-4337-6959)
Institutions
- Shanxi University (CN)
- Lund University (SE)
- Jilin University (CN)
- Tohoku University (JP)
- Peking University (CN)
- Yangtze River Delta Physics Research Center (China) (CN)
Publication Details
- Journal
- Science Advances
- Published
- 2025-09-19
- DOI
- https://doi.org/10.1126/sciadv.adw5415
- Citations
- 3
- Primary Topic
- Laser-Matter Interactions and Applications
- Type
- article
- Field-Weighted Citation Impact
- 3.74