Same-period emission and recombination in nonsequential double-recombination high-order-harmonic generation

  title={Same-period emission and recombination in nonsequential double-recombination high-order-harmonic generation},
  author={K. Hansen and Lars Bojer Madsen},
  journal={Physical Review A},
Non-sequential double recombination (NSDR) high-order harmonic generation (HHG) is studied in a molecular system. We observe a unique molecular two-electron effect with a characteristic cutoff in the HHG spectrum at higher energies than what was previously seen for NSDR HHG in atoms. The effect is corroborated with a classical model where it is found that the effect is sensitive to the molecular potential and originates from same period emission and recombination (SPEaR) of two electrons. The… 

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