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Title: Signatures of symmetry and electronic structure in high-order harmonic generation in polyatomic molecules

Abstract

We report detailed measurements of high-order harmonic generation in chloromethane molecules (CCl{sub 4}, CHCl{sub 3}, and CH{sub 2}Cl{sub 2}) to show that fingerprints of symmetry and electronic structure can be decoded from high-order harmonic generation even in complex randomly oriented molecules. In our measurements, orbital symmetries of these molecules are manifested as both extended harmonic cutoffs and a local minimum in the ellipticity dependence of the cut-off harmonics, suggesting the occurrence of quantum interferences during ionization. The harmonic spectra exhibit distinct interference minima at {approx}42 and {approx}60 eV. We attribute the former to the Cooper minimum in the photoionization cross section and the latter to intramolecular interference during the recombination process.

Authors:
; ;  [1]
  1. Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario, K1N 6N5 (Canada)
Publication Date:
OSTI Identifier:
21407878
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 81; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.81.061402; (c) 2010 The American Physical Society
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; CARBON TETRACHLORIDE; CHLOROFORM; ELECTRONIC STRUCTURE; EV RANGE; HARMONIC GENERATION; HARMONICS; INTERFERENCE; METHYL CHLORIDE; METHYLENE CHLORIDE; MOLECULES; PHOTOIONIZATION; SYMMETRY; CHLORINATED ALIPHATIC HYDROCARBONS; ENERGY RANGE; FREQUENCY MIXING; HALOGENATED ALIPHATIC HYDROCARBONS; IONIZATION; ORGANIC CHLORINE COMPOUNDS; ORGANIC COMPOUNDS; ORGANIC HALOGEN COMPOUNDS; OSCILLATIONS

Citation Formats

Wong, M. C. H., Brichta, J.-P., and Bhardwaj, V. R.. Signatures of symmetry and electronic structure in high-order harmonic generation in polyatomic molecules. United States: N. p., 2010. Web. doi:10.1103/PHYSREVA.81.061402.
Wong, M. C. H., Brichta, J.-P., & Bhardwaj, V. R.. Signatures of symmetry and electronic structure in high-order harmonic generation in polyatomic molecules. United States. doi:10.1103/PHYSREVA.81.061402.
Wong, M. C. H., Brichta, J.-P., and Bhardwaj, V. R.. 2010. "Signatures of symmetry and electronic structure in high-order harmonic generation in polyatomic molecules". United States. doi:10.1103/PHYSREVA.81.061402.
@article{osti_21407878,
title = {Signatures of symmetry and electronic structure in high-order harmonic generation in polyatomic molecules},
author = {Wong, M. C. H. and Brichta, J.-P. and Bhardwaj, V. R.},
abstractNote = {We report detailed measurements of high-order harmonic generation in chloromethane molecules (CCl{sub 4}, CHCl{sub 3}, and CH{sub 2}Cl{sub 2}) to show that fingerprints of symmetry and electronic structure can be decoded from high-order harmonic generation even in complex randomly oriented molecules. In our measurements, orbital symmetries of these molecules are manifested as both extended harmonic cutoffs and a local minimum in the ellipticity dependence of the cut-off harmonics, suggesting the occurrence of quantum interferences during ionization. The harmonic spectra exhibit distinct interference minima at {approx}42 and {approx}60 eV. We attribute the former to the Cooper minimum in the photoionization cross section and the latter to intramolecular interference during the recombination process.},
doi = {10.1103/PHYSREVA.81.061402},
journal = {Physical Review. A},
number = 6,
volume = 81,
place = {United States},
year = 2010,
month = 6
}
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