Attosecond timing of electron emission from a molecular shape resonance

Summary, in English

Shape resonances in physics and chemistry arise from the spatial confinement of a particle by a potential barrier. In molecular photoionization, these barriers prevent the electron from escaping instantaneously, so that nuclei may move and modify the potential, thereby affecting the ionization process. By using an attosecond two-color interferometric approach in combination with high spectral resolution, we have captured the changes induced by the nuclear motion on the centrifugal barrier that sustains the well-known shape resonance in valence-ionized N2. We show that despite the nuclear motion altering the bond length by only 2%, which leads to tiny changes in the potential barrier, the corresponding change in the ionization time can be as large as 200 attoseconds. This result poses limits to the concept of instantaneous electronic transitions in molecules, which is at the basis of the Franck-Condon principle of molecular spectroscopy.

• Author: S. Nandi; E. Plésiat; S. Zhong; A. Palacios; D. Busto; M. Isinger; L. Neoričić; C. L. Arnold; R. J. Squibb; R. Feifel; P. Decleva; A. L'Huillier; F. Martín; M. Gisselbrecht
• Department/s: Atomic Physics; NanoLund: Centre for Nanoscience; Synchrotron Radiation Research
• Publishing year: 2020
• Language: English
• Pages: 7762-7762
• Publication/Series: Science Advances
• Volume: 6
• Issue: 31
• Links: http://dx.doi.org/10.1126/sciadv.aba7762
• Document type: Journal article
• Publisher: American Association for the Advancement of Science (AAAS)
• Topic: Atom and Molecular Physics and Optics
• Status: Published
• Project: Attosecond chronoscopy of electron wave-packets probing entanglement and time-ordering of quantum processes
• ISBN/ISSN/Other: ISSN: 2375-2548