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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
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Multicomponent dynamics of coupled quantum subspaces and field-induced molecular ionizations
Thanh-Tung Nguyen-Dang1, Jérémy Viau-Trudel1
1Département de Chimie, Université Laval, Québec, Québec G1K 7P4, Canada.
The Journal of Chemical Physics
|January 7, 2014
Summary
We developed a new method to model how intense laser pulses ionize atoms and molecules. This approach reveals how electron momentum distributions change with laser pulse duration, offering insights into ionization dynamics.
Area of Science:
- Quantum Chemistry
- Atomic and Molecular Physics
- Computational Physics
Background:
- Understanding multi-electron ionization dynamics is crucial for controlling chemical reactions with light.
- Accurate theoretical models are needed to simulate complex electron behavior under intense laser fields.
Purpose of the Study:
- To introduce a novel theoretical framework for describing successive ionization steps in many-electron systems.
- To investigate the impact of ultrashort laser pulse characteristics on ionization pathways and photoelectron spectra.
Main Methods:
- Developed a hierarchy of successive two-subspace Feshbach partitions for the N-electron Hilbert space.
- Solved the partitioned time-dependent Schrödinger equation using a short-time unitary algorithm.
- Applied the method to a two-active-electron molecular model with few-cycle extreme ultraviolet (XUV) pulses.
Main Results:
- Demonstrated a flexible partitioning scheme allowing different theoretical treatments for various subspaces.
- Observed distinct photoelectron momentum and kinetic-energy distributions based on XUV pulse width.
- Characterized transitions between impulsive ionization and multiphoton above-threshold ionization regimes.
Conclusions:
- The new partitioning method provides a versatile tool for studying complex ionization processes.
- Pulse duration significantly influences electron emission characteristics, bridging impulsive and continuous-wave ionization limits.
- This work advances the theoretical understanding of light-driven electron dynamics in molecules.
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