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Zeptosecond birth time delay in molecular photoionization
Sven Grundmann1, Daniel Trabert2, Kilian Fehre2
1Institut für Kernphysik, Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt, Germany. grundmann@atom.uni-frankfurt.de jahnke@atom.uni-frankfurt.de doerner@atom.uni-frankfurt.de.
Science (New York, N.Y.)
|October 16, 2020
Summary
Electron launch times during photoionization vary within a molecule. This study reveals a zeptosecond-scale delay in electron emission from molecular hydrogen due to photon travel time.
Area of Science:
- Quantum mechanics
- Attosecond science
- Light-matter interactions
Background:
- Photoionization, a fundamental light-matter interaction, involves photon absorption and electron ejection.
- Attosecond experiments reveal time delays in electron emission from different molecular orbitals or directions.
- The precise timing of electron ejection within a molecule remains an open question.
Purpose of the Study:
- To investigate the temporal dynamics of electron emission during photoionization within a molecule.
- To determine if electrons are ejected simultaneously from different parts of a molecule.
- To resolve attosecond-scale time delays in electron emission from molecular hydrogen.
Main Methods:
- Utilizing an electron interferometric technique.
- Performing attosecond pump-probe spectroscopy.
- Analyzing the interference patterns of ejected electrons.
Main Results:
- Demonstrated that electron launch times are not simultaneous across a molecular orbital.
- Quantified a birth time delay of 247 zeptoseconds for molecular hydrogen.
- Resolved the time delay between electron emission from the two centers of the hydrogen molecule.
Conclusions:
- Photon travel time across a molecule influences electron birth time during photoionization.
- Electron emission is not instantaneous but exhibits temporal delays dependent on molecular structure.
- This research provides new insights into the ultrafast dynamics of light-matter interactions in molecules.
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