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Updated: Jul 15, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Multiphoton femtosecond phase-coherent two-dimensional electronic spectroscopy.
Chunqiang Li1, Wolfgang Wagner, Maria Ciocca
1Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA.
The Journal of Chemical Physics
|May 5, 2007
Summary
This study compares one-photon and two-photon spectroscopy of Coumarin 102. Differences in spectral shapes reveal distinct selection rules for each excitation method.
Area of Science:
- Physical Chemistry
- Spectroscopy
- Organic Electronics
Background:
- Organic laser dyes are crucial for tunable light sources.
- Understanding their photophysical properties is essential for material design.
- Two-dimensional electronic spectroscopy (2DES) provides insights into molecular dynamics.
Purpose of the Study:
- To compare one-photon and two-photon 2D Fourier transform electronic spectra.
- To investigate the influence of excitation wavelength on spectral features.
- To elucidate the role of selection rules in different spectroscopic techniques.
Main Methods:
- Utilized collinear optical pulse sequences and phase cycling.
- Acquired 400 nm one-photon and 800 nm two-photon 2D electronic spectra.
- Studied the organic laser dye Coumarin 102 in methanol solution.
Main Results:
- Observed differences in photon echo peak positions between one-photon and two-photon spectra.
- Noted variations in spectral shapes correlating with excitation method.
- These spectral differences highlight the impact of one-photon vs. two-photon selection rules.
Conclusions:
- One-photon and two-photon excitation exhibit distinct spectral signatures.
- The observed spectral differences are directly attributable to differing selection rules.
- This comparative spectroscopic approach enhances understanding of molecular excitation processes.
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