title: Polarization properties of below-threshold harmonics from aligned molecules H2+ in linearly polarized laser fields.
abstract: We investigate the polarization properties of below-threshold harmonics from aligned molecules in linearly polarized laser fields numerically and analytically. We focus on lower-order harmonics (LOHs). Our simulations show that the ellipticity of below-threshold LOHs depends strongly on the orientation angle and differs significantly for different harmonic orders. Our analysis reveals that this LOH ellipticity is closely associated with resonance effects and the axis symmetry of the molecule. These results shed light on the complex generation mechanism of below-threshold harmonics from aligned molecules.
authors.forename: Fulong
authors.initials: F
authors.lastname: Dong
authors.forename: Yiqun
authors.initials: Y
authors.lastname: Tian
authors.forename: Shujuan
authors.initials: S
authors.lastname: Yu
authors.forename: Shang
authors.initials: S
authors.lastname: Wang
authors.forename: Shiping
authors.initials: S
authors.lastname: Yang
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Chen