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Updated: May 13, 2026
10:17
20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier
Published on: July 12, 2017
Enhanced narrow-bandwidth emission during high-order harmonic generation from aligned molecules
Chaojin Zhang1, Jinping Yao, Fadhil A Umran
1School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China. chaojinzhang@163.com
Optics Express
|March 14, 2013
Summary
We theoretically investigated high-harmonic generation (HHG) in oxygen molecules. Narrow-bandwidth HHG emission can be controlled by laser fields and molecular alignment, potentially reconstructing molecular orbitals.
Area of Science:
- Quantum Optics
- Molecular Physics
- Attosecond Science
Background:
- High-harmonic generation (HHG) is a crucial nonlinear optical process for generating coherent extreme ultraviolet and X-ray radiation.
- Understanding molecular HHG is key to probing ultrafast electronic dynamics and molecular structure.
- Controlling HHG spectra offers pathways to novel light sources and molecular orbital imaging.
Purpose of the Study:
- To theoretically investigate the selective enhancement of narrow-bandwidth high-harmonic generation (HHG) in aligned O(2) molecules.
- To explore the control mechanisms for enhanced HHG emission using orthogonal-polarized two-color laser fields.
- To assess the potential of narrow-bandwidth HHG as a method for reconstructing molecular orbitals.
Main Methods:
- Theoretical modeling of high-harmonic generation in aligned O(2) molecules.
- Utilizing an orthogonal-polarized two-color laser field configuration.
- Analyzing the influence of molecular alignment angle, laser intensity, and relative phase on HHG spectra.
Main Results:
- Selective enhancement of narrow-bandwidth HHG emission near the spectral cutoff was achieved.
- The enhanced emission was found to be controllable via molecular alignment angle, laser intensity, and relative phase.
- A strong dependence of the narrow-bandwidth HHG on molecular alignment was observed.
Conclusions:
- Narrow-bandwidth HHG in O(2) molecules can be effectively controlled by external laser parameters and molecular orientation.
- The observed dependence on molecular alignment suggests that narrow-bandwidth HHG encodes information about molecular orbitals.
- This technique presents a potential alternative method for the reconstruction of O(2) molecular orbitals.
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