title: Multielectron contributions in elliptically polarized high-order harmonic emission from nitrogen molecules.
abstract: We have studied the polarization and ellipticity of high-order harmonics from nitrogen molecules using the time-dependent density functional theory. The results of our numerical calculations are in excellent agreement with the data of recent experiments. The theoretical analysis of our results reveals that at least three contributions, namely those from the HOMO, the HOMO-1, and the HOMO-2 orbitals, contribute to the observed high harmonic spectra. Furthermore, we confirm that a proper account of the distribution of the alignment in the molecular ensemble is necessary to obtain agreement with the experimental data.
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Xia
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Jaroń-Becker