Suppression of Recollision-Excitation Ionization in Nonsequential Double Ionization of Molecules by Mid-Infrared Laser Pulses

【摘要】 The electron dynamics in strong field non-sequential double ionization of nitrogen molecules is investigated with the three-dimensional(3D) classical ensemble model.The numerical results show that the longitudinal momentum spectrum of the doubly charged ions evolves from a wide single-hump structure at the near-infrared(NIR) regime into a double-hump structure when the wavelength enters the mid-infrared(MIR) regime.Back analysis reveals that in the MIR regime,the recollision excitation with subsequent ionization(RESI) is strongly suppressed with increasing wavelength,which results in the double-hump structure of the ions momentum spectra.This doublehump structure becomes more pronounced as the wavelength further increases because the contribution of the RESI further decreases.更多还原

【Abstract】 The electron dynamics in strong field non-sequential double ionization of nitrogen molecules is investigated with the three-dimensional(3D) classical ensemble model.The numerical results show that the longitudinal momentum spectrum of the doubly charged ions evolves from a wide single-hump structure at the near-infrared(NIR) regime into a double-hump structure when the wavelength enters the mid-infrared(MIR) regime.Back analysis reveals that in the MIR regime,the recollision excitation with subsequent ionization(RESI) is strongly suppressed with increasing wavelength,which results in the double-hump structure of the ions momentum spectra.This doublehump structure becomes more pronounced as the wavelength further increases because the contribution of the RESI further decreases.更多还原