Dissociative double ionization of CO in orthogonal two-color laser fields

Abstract

We experimentally investigate dissociative double ionization of CO by a phase-controlled orthogonal twocolor (OTC) laser pulse. Directional breaking of doubly ionized CO as a function of both kinetic energy and emission direction of the nuclear fragments is observed in the polarization plane steered by the laser phase. It is attributed to the dominating sequential double ionization at the maximum strength and nonsequential double ionization at a relatively weak strength of the spatiotemporally shaped oscillating laser field pointing to various directions. Our results are interesting not only for two-dimensional control of directional bond breaking, but also strengthen our understanding of strong-field sequential and nonsequential double ionization of molecules which are spatiotemporally streaked to various directions and kinetic energies by an OTC laser pulse.

Two-color phase-of-the-phase spectroscopy in the multiphoton regime

“…For ξ = 0, the known result [32] for the PES without the 2ω component is obtained. The rate (15) has indeed the same structure as the assumed yield in (2), that is…”

“…5. The checkerboard structure is more pronounced in the analytical result because of the flat-top, infinite-pulse assumption on which (15) is based. For the numerical evaluation, the δ distribution in (15) was replaced by a Gaussian exp[−(p 2 /2+I p +U p −nω) 2 /a 2 ]/a √ π with a = 1/20, and the sum over n was restricted to 30 n=−30 .…”

Sub-cycle directional control of the dissociative ionization of H2in tailored femtosecond laser fields

“…However, starting from neutral hydrogen molecules, the exact modeling becomes difficult due to the complex entanglement between the ionization and dissociation processes induced by the strong laser fields, which are hard to separate in experiments. Experimental schemes were developed to disentangle the role of laser coupling in the ionization and dissociation steps [33,34,49]. This exemplifies that there is still large room for the improvement of experimental techniques.…”

“…For instance, a multi-cycle two-color laser field by combining the 800 nm component with its orthogonally polarized SH signal is shown in figures 2(c) and (d). With such laser field electron localization in hydrogen can be steered in 2D [48], which also permits to distinguish sequential and non-sequential double ionization of molecules [49]. The electron excited by one color can be streaked by the other color in the perpendicular direction, therefore providing more degrees of freedom for the directional control.…”

Coulomb exploded directional double ionization of N2O molecules in multicycle femtosecond laser pulses*

“…[10][11][12][13][14][15] Recently, the directional bond breaking control was realized in two-dimensional space by using phase-controlled orthogonally or circularly polarized two-color laser fields. [16][17][18] However, the molecular bond breaking control mainly focused on the diatomic molecules, and only few triatomic [19][20][21] and polyatomic molecules [22][23][24] were investigated which are more interesting with rich dynamics.…”