Uncovering multiple orbitals influence in high harmonic generation from aligned N${}_2$

Abstract

Recent measurements on high-order harmonic generation (HHG) from N${}_2$ aligned perpendicular to the driving laser polarization [B. K. McFarland {\it el al}, Science {\bf 322}, 1232 (2008)] have shown a maximum at the rotational half-revival. This has been interpreted as the signature of the HHG contribution from the molecular orbital just below the highest occupied molecular orbital (HOMO). By using the recently developed quantitative rescattering theory combined with accurate photoionization transition dipoles, we show that the maximum at the rotational half-revival is indeed associated with the HOMO-1 contribution. Our results also show that the HOMO-1 contribution becomes increasingly more important near the HHG cutoff and therefore depends on the laser intensity.

9 pages, 4 figures

References in corpus (7)

• Accurate retrieval of structural information from laser-induced photoelectron and high-harmonic spectra by few-cycle laser pulses
• Quantitative Rescattering Theory for high-order harmonic generation from molecules
• Quantitative rescattering theory for laser-induced high-energy plateau photoelectron spectra
• Extraction of the species dependent dipole moment from high-order harmonic spectra in rare gas atoms
• High-harmonic generation from arbitrarily oriented diatomic molecules including nuclear motion and field-free alignment
• Probing molecular frame photoionization via laser generated high-order harmonics from aligned molecules
• Theory of high-order harmonic generation from molecules by intense laser pulses