Role of the Permanent Dipole Moment in Coulomb Explosion

Abstract

By numerically solving the non-Born-Oppenheimer time-dependent Schrödinger equation in a few-cycle chirped laser field (5-fs, 800-nm), the effect of the permanent dipole moment on the Coulomb explosion is studied by the kinetic-energy-release spectra with the "virtual detector" method. The results indicate that with the effect of the permanent dipole moment, different multiphoton processes for heteronuclear and homonuclear diatomic molecular ions may take place when the wave packets transit from the ground state (1𝑠𝜎𝑔) to the first excited state (2𝑝𝜎𝑢), and then move along the excited potential curve, and finally charge-resonant enhanced ionization occurs at critical internuclear distance. As a result, despite the similar ionization probabilities for these two systems at higher vibrational level with larger chirp parameter 𝛽, the structure of the Coulomb explosion spectrum for the former is prominently different from that for the latter.

Manipulation of the recombination channels and isolated attosecond pulse generation from HeH2+ with multicycle combined field

“…μ n and μ e are the reduced masses with M He and M H the masses of He and H. The soft parameters a = 0.01 and b = 0.3 [23]. The time-dependent electron-nuclear wave function ψ(R, z; t) is obtained by using the standard second-order split operator method [26][27][28][29][30]…”

Investigation of electron localization in harmonic emission from asymmetric molecular ion

“…The dynamics of a molecule in a strong field has been a popular topic in recent years. [1] Many interesting phenomena, such as above-threshold dissociation and below-threshold dissociation, [2][3][4] bond hardening and bond softening, [5,6] high-order harmonic generation (HHG), [7][8][9] and Coulomb explosion [10,11] have been investigated. The HHG is the most attractive effect to be used to generate isolated attosecond pulses.…”