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arXiv · 2109.01581

Complete characterization of multi-channel single photon ionization

Abstract

Ionization of atoms and molecules by absorption of a light pulse results in electron wavepackets carrying information on the atomic or molecular structure as well as on the dynamics of the ionization process. These wavepackets can be described as a coherent sum of waves of given angular momentum, called partial waves, each characterized by an amplitude and a phase. The complete characterization of the individual angular momentum components is experimentally challenging, requiring the analysis of the interference between partial waves both in energy and angle. Using a two-photon interferometry technique based on extreme ultraviolet attosecond and infrared femtosecond pulses, we characterize the individual partial wave components in the photoionization of the 2p shell in neon. The study of the phases of the angular momentum channels allows us to unravel the influence of short-range, correlation and centrifugal effects. This approach enables the complete reconstruction of photoionization electron wavepackets in time and space, providing insight into the photoionization dynamics.

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Jasper Peschel, David Busto, Marius Plach, Mattias Bertolino, Maria Hoflund, Sylvain Maclot, Jimmy Vinbladh, Hampus Wikmark, Felipe Zapata, Eva Lindroth, Mathieu Gisselbrecht, Jan Marcus Dahlström, Anne L'Huillier, Per Eng-Johnsson. 2021-09-03. Complete characterization of multi-channel single photon ionization. https://arxiv.org/abs/2109.01581

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