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Updated: Jun 23, 2026
10:52
Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Non-sequential double ionization of helium and related wave-function dynamics obtained from a five-dimensional grid
Optics Express
|May 7, 2009
Summary
Strong laser light causes helium atoms to lose two electrons, primarily when the light
Area of Science:
- Quantum mechanics
- Atomic physics
- Laser-matter interactions
Background:
- Understanding atomic behavior under intense laser fields is crucial.
- Helium's two-electron system provides a fundamental model for atomic ionization dynamics.
Purpose of the Study:
- Investigate the mechanism of non-sequential double ionization in helium.
- Analyze electron behavior under strong, pulsed laser light (390 nm and 800 nm).
Main Methods:
- Numerical integration of the time-dependent Schroedinger equation.
- Simulation of two three-dimensional electrons in helium.
Main Results:
- Non-sequential double ionization peaks when the laser's electric field is strongest.
- Double ionization initiates in the second laser cycle and stabilizes over multiple cycles.
- Evidence suggests electron recollision, potentially via long trajectories, is essential.
Conclusions:
- Electron recollision is a key process in helium's non-sequential double ionization.
- The dynamics are dependent on laser pulse characteristics, including intensity and duration.
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