Controlling harmonic distributions from H2+ driven by linearly and circularly polarized laser fields

Highlights: • Spatial distributions of molecular high-order harmonic spectra. • Numerically solving the two dimensional time-dependent Schrödinger equation. • The time–frequency analyses of the harmonics emission. • Harmonic emission from the linearly and the improved circularly polarized laser fields. - Abstract: The spatial distributions of the high-order harmonics from H₂⁺ driven by the linearly and the circularly polarized laser fields have been theoretically investigated. It is found that when the molecular axis parallels to the polarized direction of the linearly polarized laser field, the contributions of the harmonics are mainly from the negative-H and the positive-H for the cases of E(t) > 0 and E(t) 2⁺.