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arXiv · 2010.08298

Zeptosecond Birth Time Delay in Molecular Photoionization

Sven Grundmann·Daniel Trabert·Kilian Fehre·Nico Strenger·Andreas Pier·Leon Kaiser·Max Kircher·Miriam Weller·Sebastian Eckart·Lothar Ph. H. Schmidt·Florian Trinter·Till Jahnke·Markus S. Schöffler·Reinhard Dörner
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Abstract

Photoionization is one of the fundamental light-matter interaction processes in which the absorption of a photon launches the escape of an electron. The time scale of the process poses many open questions. Experiments found time delays in the attosecond ($10^{-18}$ s) domain between electron ejection from different orbitals, electronic bands, or in different directions. Here, we demonstrate that across a molecular orbital the electron is not launched at the same time. The birth time rather depends on the travel time of the photon across the molecule, which is 247 zeptoseconds ($10^{-21}$ s) for the average bond length of H$_2$. Using an electron interferometric technique, we resolve this birth time delay between electron emission from the two centers of the hydrogen molecule.

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Sven Grundmann, Daniel Trabert, Kilian Fehre, Nico Strenger, Andreas Pier, Leon Kaiser, Max Kircher, Miriam Weller, Sebastian Eckart, Lothar Ph. H. Schmidt, Florian Trinter, Till Jahnke, Markus S. Schöffler, Reinhard Dörner. 2020-10-16. Zeptosecond Birth Time Delay in Molecular Photoionization. https://doi.org/10.1126/science.abb9318

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