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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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Probing nonadiabatic effects in strong-field tunnel ionization
R Boge1, C Cirelli1, A S Landsman1
1Physics Department, ETH Zurich, 8093 Zurich, Switzerland.
Physical Review Letters
|August 29, 2014
Summary
This study experimentally tested theories of strong-field ionization in helium. Results show nonadiabatic theories fail, while adiabatic assumptions accurately describe tunnel ionization under intense laser fields.
Area of Science:
- Atomic and Molecular Physics
- Quantum Optics
- Strong-Field Physics
Background:
- Strong-field ionization is crucial for understanding matter-light interactions.
- Tunnel ionization theories often extend the adiabatic approximation, but their validity in the multiphoton regime is debated.
Purpose of the Study:
- To experimentally validate theories extending the tunneling approximation into the multiphoton regime for strong-field ionization.
- To investigate the sensitivity of electron observables to nonadiabatic effects in tunnel ionization.
Main Methods:
- Experimentally probed strong-field ionization of helium using elliptically polarized laser pulses.
- Analyzed the influence of the ion potential on the released electron as a sensitive observable.
Main Results:
- Observed experimental trends that contradict proposed nonadiabatic theories over a wide intensity range.
- Found that adiabatic assumptions align with experimental data for tunnel ionization.
Conclusions:
- The proposed nonadiabatic theories for strong-field ionization are not supported by experimental evidence in helium.
- The adiabatic approximation remains a valid framework for describing tunnel ionization in this regime.
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