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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Angle-resolved high-order above-threshold ionization of a molecule: sensitive tool for molecular characterization
M Busuladzić1, A Gazibegović-Busuladzić, D B Milosević
1Medical Faculty, University of Sarajevo, Cekalusa 90, 71000 Sarajevo, Bosnia and Herzegovina.
Physical Review Letters
|June 4, 2008
Summary
Strong-field approximation for molecular ionization reveals electron rescattering. This phenomenon, dependent on molecular orbital symmetry, allows for determining internuclear separation in N2 but is absent in O2 under specific laser conditions.
Area of Science:
- Atomic, Molecular, and Optical Physics
- Quantum Mechanics
- Laser-Induced Phenomena
Background:
- Intense laser fields interacting with diatomic molecules can lead to electron ionization.
- The behavior of the ionized electron, including rescattering, is crucial for understanding molecular response.
- Previous models often simplified electron dynamics, neglecting rescattering effects.
Purpose of the Study:
- To generalize the strong-field approximation to incorporate electron rescattering from diatomic molecular ions.
- To investigate the influence of molecular orbital symmetry on the ionization spectrum and interference structure.
- To explore the potential for determining molecular properties, such as internuclear separation, using this approach.
Main Methods:
- Generalization of the strong-field approximation to include electron-ion rescattering.
- Theoretical modeling of ionization spectra for diatomic molecules (N2 and O2) under intense laser fields.
- Analysis of the dependence of spectral features on laser polarization and molecular orbital symmetry.
Main Results:
- The ionization spectrum and interference structure are highly sensitive to the ground state molecular orbital symmetry.
- For N2, a distinct minimum in the emission spectrum is observed when laser polarization is perpendicular to the molecular axis, persisting after focal averaging.
- This spectral minimum in N2 allows for the determination of internuclear separation, while rescattering is found to be absent for O2 under identical conditions.
Conclusions:
- Electron rescattering plays a significant role in intense-field molecular ionization, with its presence and effects dictated by molecular symmetry.
- The observed spectral minimum in N2 provides a novel pathway for measuring internuclear distances.
- The distinct differences in rescattering behavior between N2 and O2 highlight the importance of considering specific molecular properties in strong-field interactions.
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