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Title: Attosecond photoionization delays in the vicinity of molecular Feshbach resonances
Temporal delays extracted from photoionization phases are currently determined with attosecond resolution by using interferometric methods. Such methods require special care when photoionization occurs near Feshbach resonances due to the interference between direct ionization and autoionization. Although theory can accurately handle these interferences in atoms, in molecules, it has to face an additional, so far insurmountable problem: Autoionization is slow, and nuclei move substantially while it happens, i.e., electronic and nuclear motions are coupled. Here, we present a theoretical framework to account for this effect and apply it to evaluate time-resolved and vibrationally resolved photoelectron spectra and photoionization phases of N2irradiated by a combination of an extreme ultraviolet (XUV) attosecond pulse train and an infrared pulse. We show that Feshbach resonances lead to unusual non–Franck-Condon vibrational progressions and to ionization phases that strongly vary with photoelectron energy irrespective of the vibrational state of the remaining molecular cation.  more » « less
Award ID(s):
1912507
PAR ID:
10487978
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Science Journals, AAAS
Date Published:
Journal Name:
Science Advances
Volume:
9
Issue:
15
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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