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Physical Review A

Asymmetric dissociative single ionization of argon dimers in two-color femtosecond laser fields

Junyang Ma, Shuqi Li, Xueying Li, Fan Yang, Yan Yang, Zhenrong Sun

Published Dec 10, 2024• 3 citations
Publisher

Abstract

Coherent control of the fragmentation of van der Waals--bound rare-gas dimers is crucial for gaining insights into the properties of weakly bound complexes. In this study, we experimentally investigate the directional dissociative single ionization of argon dimers, employing relative phase-controlled linearly and elliptically polarized two-color femtosecond laser fields. The emission direction of the ionic fragments is manipulated by adjusting the relative phase of the two-color laser fields. We attribute the observed asymmetric pattern to the interference between different dissociation pathways, corresponding to the nuclear wave packet propagating on the gerade and ungerade states, respectively. The relative phase-dependent asymmetries observed in linearly and elliptically polarized two-color laser fields exhibit similarities, suggesting a limited role of electron recollision. Our results highlight the role of nuclear wave-packet interference in the directional fragmentation of rare-gas dimers, and they promote the possibility of coherent control of van der Waals bond cleavage in chemical reactions.

DOI
10.1103/physreva.110.063108

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