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Multielectron contributions in elliptically polarized high-order harmonic emission from nitrogen molecules
Optics Letters
|April 3, 2014
Summary
High-order harmonic generation in nitrogen molecules was studied using time-dependent density functional theory. Results show contributions from multiple orbitals and highlight the importance of molecular alignment for accurate experimental agreement.
Area of Science:
- Quantum mechanics
- Molecular physics
- Nonlinear optics
Background:
- High-order harmonic generation (HHG) is a crucial process in nonlinear optics.
- Understanding the electronic structure contributions to HHG is essential for controlling light-matter interactions.
- Nitrogen molecules serve as a fundamental system for studying molecular HHG dynamics.
Purpose of the Study:
- To investigate the polarization and ellipticity of high-order harmonics from nitrogen molecules.
- To theoretically elucidate the contributing electronic orbitals to the observed high harmonic spectra.
- To validate theoretical models against experimental data for molecular HHG.
Main Methods:
- Utilizing time-dependent density functional theory (TD-DFT) for numerical calculations.
- Analyzing the polarization and ellipticity of generated high-order harmonics.
- Comparing theoretical predictions with experimental measurements.
Main Results:
- Numerical calculations show excellent agreement with experimental data.
- Identified contributions from the highest occupied molecular orbital (HOMO), HOMO-1, and HOMO-2 orbitals to the spectra.
- Confirmed the necessity of considering the distribution of molecular alignment in ensembles.
Conclusions:
- The theoretical model accurately reproduces experimental observations of high-order harmonic generation in nitrogen.
- Multiple electronic orbitals play a significant role in shaping the harmonic spectra.
- Accurate modeling of molecular alignment distributions is critical for precise theoretical predictions in HHG studies.
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