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Physical Review A

Strong-field ionization of diatomic molecules in orthogonally polarized two-color fields

Mingming Liu, Meng Han, Peipei Ge, Chaoxiong He, Qihuang Gong, Yunquan Liu

Published Jun 20, 2018• 19 citations
Publisher

Abstract

We study the control of ionization dynamics of aligned ${\mathrm{N}}_{2}$ and ${\mathrm{O}}_{2}$ molecules in orthogonally polarized two-color (OTC) fields and calculate the photoelectron momentum distributions of molecules by solving the time-dependent Schr\"odinger equation and with a semiclassical model. In contrast with that of atoms in the OTC field, we show that the photoelectron momentum distribution is essentially dependent on the molecular outmost orbital, the alignment angle, and the phase of the OTC field. We illustrate the controlling of the molecular frame photoelectron angular distributions and the temporal and spatial double-slit interference effect for strong-field ionization of ${\mathrm{N}}_{2}$ molecules. For ${\mathrm{O}}_{2}$ molecules, it is shown that the ionization wave packets are splitting. The temporal and spatial double-slit interference effect is always present for ${\mathrm{O}}_{2}$, which is not able to be turned off using the OTC field. This work would have implications for probing molecular structures with a two-color synthesized laser field.

DOI
10.1103/physreva.97.063416

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