Sub-cycle attosecond control in frustrated double ionization of molecules with orthogonally polarized two-color laser fields

TL;DR

This study demonstrates precise sub-cycle control of frustrated double ionization in a triatomic molecule using orthogonally polarized two-color laser fields, revealing detailed electron tunneling dynamics within a laser cycle.

Contribution

It introduces a semi-classical model for controlling and mapping electron tunneling times in molecular ionization with orthogonal two-color laser fields.

Findings

Controlled FDI probability via pulse delay.

Momentum distribution reveals tunneling timing.

Distinct features map to electron tunneling events.

Abstract

We demonstrate sub-cycle control of frustrated double ionization (FDI) in the two-electron triatomic molecule D$_3^+$ when driven by two orthogonally polarized two-color laser fields. We employ a three-dimensional semi-classical model that fully accounts for the electron and nuclear motion in strong fields. We control FDI triggered by a strong near-infrared laser field with a weak mid-infrared laser field. This control as a function of the time delay between the two pulses is demonstrated when the FDI probability and the distribution of the momentum of the escaping electron along the mid-infrared laser field are considered in conjunction. We find that the momentum distribution of the escaping electron has a hive-shape with features that can accurately be mapped to the time one of the two electrons tunnel-ionizes at the start of the break-up process. This mapping distinguishes consecutive tunnel-ionization times within a cycle of the mid-infrared laser field.