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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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"Stirred, Not Shaken": Vibrational Coherence Can Speed Up Electronic Absorption
Bo Y Chang1, Seokmin Shin1, Ignacio R Sola2
1School of Chemistry (BK21+), Seoul National University , Seoul 151-747, Republic of Korea.
The Journal of Physical Chemistry. A
|August 11, 2015
Summary
Initial vibrational coherence in molecules significantly enhances ultrafast laser absorption rates. This effect is absent with long laser pulses, highlighting the importance of pulse characteristics in molecular light absorption.
Area of Science:
- Physical Chemistry
- Molecular Spectroscopy
- Quantum Control
Background:
- Laser control schemes are crucial for manipulating molecular processes.
- Understanding electronic absorption in multilevel systems is fundamental.
- Previous work proposed parallel transfer for ultrafast absorption.
Purpose of the Study:
- To develop an analytical model for molecular electronic absorption.
- To investigate the role of initial vibrational coherence in absorption.
- To analyze the influence of laser pulse characteristics (ultrashort vs. long) on absorption enhancement.
Main Methods:
- Development of a refined analytical model for electronic absorption.
- Incorporation of initial vibrational coherence effects.
- Numerical simulations of optical transitions in the Na2 molecule.
Main Results:
- Initial vibrational coherence enhances absorption rate and yield with ultrashort pulses when coherence phases are considered.
- The role of initial coherence diminishes significantly when using a single long laser pulse.
- Theoretical predictions validated through numerical simulations on Na2.
Conclusions:
- Vibrational coherence is a key factor for optimizing ultrafast light absorption in molecules.
- Laser pulse properties critically determine the influence of initial molecular coherence.
- The developed model provides insights into quantum control of molecular optical transitions.
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