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Updated: Jun 22, 2026
08:22
Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Speed-up collisions in strong-field double ionization.
Optics Express
|June 2, 2009
Summary
This study compares quantum and classical models of double ionization in helium. Quantum models show speed-up collisions contribute to ionization, while classical models reveal distinct pathways for these events.
Area of Science:
- Atomic, Molecular, and Optical Physics
- Quantum Mechanics
- Computational Physics
Background:
- Strong laser fields induce complex electron dynamics in atoms.
- Double ionization (DI) is a key process in strong-field physics.
- Recollision mechanisms play a crucial role in DI.
Purpose of the Study:
- To compare quantum and classical models of double ionization in helium.
- To investigate the role of recollision processes in DI.
- To analyze the pathways leading to "with-the-force" doubly ionizing collisions.
Main Methods:
- Comparative analysis of quantum and classical simulations.
- Focus on aligned-electron helium in strong laser fields.
- Classification of electron trajectories during recollision.
Main Results:
- Quantum models confirm a small but persistent DI contribution from speed-up collisions.
- Classical modeling reveals "with-the-force" DI collisions involve two-electron trajectories.
- Two categories of trajectories identified: direct excitation and recapture.
- Quantum simulations favor the direct excitation pathway over recapture.
Conclusions:
- Classical and quantum models show agreement on the occurrence of speed-up collisions in DI.
- Trajectory analysis provides insights into the mechanisms of DI.
- The quantum system demonstrates a preference for direct excitation in DI events under the studied conditions.
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