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arXiv · 2001.07513

Dissecting strong-field excitation dynamics with atomic-momentum spectroscopy

A. W. Bray·U. Eichmann·S. Patchkovskii
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Abstract

Observation of internal quantum dynamics relies on correlations between the system being observed and the measurement apparatus. We propose using the center-of-mass (c.m.) degrees of freedom of atoms and molecules as a "built-in" monitoring device for observing their internal dynamics in non-perturbative laser fields. We illustrate the idea on the simplest model system - the hydrogen atom in an intense, tightly-focused infrared laser beam. To this end, we develop a numerically-tractable, quantum-mechanical treatment of correlations between internal and c.m. dynamics. We show that the transverse momentum records the time excited states experience the field, allowing femtosecond reconstruction of the strong-field excitation process. The ground state becomes weak-field seeking, an unambiguous and long sought-for signature of the Kramers-Henneberger regime.

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A. W. Bray, U. Eichmann, S. Patchkovskii. 2020-01-21. Dissecting strong-field excitation dynamics with atomic-momentum spectroscopy. https://doi.org/10.1103/physrevlett.124.233202

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