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arXiv · 1912.04978

Control of the Ion Polarization in the Pump-Probe Ionization of Helium

Saad Mehmood·Eva Lindroth·Luca Argenti
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Abstract

Attosecond pump-probe ionization process can be used to prepare atomic ions in the coherent superposition of states with opposite parity. The multiphoton shake-up ionization of Helium, in particular, generates ions with same principal quantum number and a net dipole moment that evolves on a time scale of few picoseconds, due to spin-orbit coupling. In this work we use an ab initio time-dependent close-coupling code to study how the coherence between levels of Helium ion can be controlled from the parameters of the ionizing-pulse sequence. The observed periodic revivals, on a picosecond time scale, of the ion dipole moment gives access to the study of the ionization of oriented targets.

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Saad Mehmood, Eva Lindroth, Luca Argenti. 2019-12-10. Control of the Ion Polarization in the Pump-Probe Ionization of Helium. https://arxiv.org/abs/1912.04978

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