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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
High harmonic spectroscopy of the Cooper minimum in molecules
M C H Wong1, A-T Le, A F Alharbi
1Department of Physics, University of Ottawa, Ottawa, Ontario, Canada.
Physical Review Letters
|February 5, 2013
Summary
This study investigates the Cooper minimum (CM) in molecules using high harmonic generation. Researchers observed the CM in specific molecules and used it to probe electron localization, finding it influenced by the molecular environment.
Area of Science:
- Atomic and Molecular Physics
- Quantum Optics
- Chemical Physics
Background:
- The Cooper minimum (CM) is a phenomenon typically studied in atomic systems.
- High harmonic generation (HHG) is a powerful technique for probing electronic structures.
Purpose of the Study:
- To experimentally and theoretically investigate the Cooper minimum (CM) in molecules using HHG.
- To explore the CM's potential for probing electron localization in molecular systems.
Main Methods:
- Utilizing high harmonic generation (HHG) with near-infrared light pulses (1.3–1.8 μm).
- Comparing experimental high harmonic spectra with theoretical calculations and known photoionization cross sections.
- Analyzing electron localization in chlorine-containing molecules.
Main Results:
- Demonstrated the Cooper minimum (CM) in CS(2) at ~42 eV and CCl(4) at ~40 eV.
- Confirmed the CM's occurrence through comparison with partial photoionization cross sections and theoretical calculations.
- Showcased the CM's sensitivity to electron localization and molecular environment in Cl-containing molecules.
Conclusions:
- The Cooper minimum (CM) is observable and applicable in molecular systems using HHG.
- HHG-induced CM provides insights into electron localization and molecular structure.
- The molecular environment significantly influences the Cooper minimum's characteristics in molecules.
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