Above-threshold dissociation of the molecular ion HD+ in a moderate-intensity femtosecond laser field from the calculation of time-of-flight spectra

The dissociation of the molecular ion HD+ in moderate-intensity laser pulses is studied using the time-dependent quantum wave-packet method. Simulations of the time-of-flight (TOF) neutral atom spectra produced from dissociation of the v=10 vibrational state at a laser intensity of 1012W/cm2 and from v=0 at the intensity of 5×1012W/cm2 are calculated. Good agreement is found with previous experimental results [P. A. Orr et al., Phys. Rev. Lett. 98, 163001 (2007) and J. D. Alexander et al., J. Phys. B 42, 154027 (2009)]. Furthermore, the kinetic energy distribution of the dissociated fragments of molecular ion HD+ is studied within the moderate laser-intensity region from 1012 to 5×1012W/cm2by considering initial vibrational states from v=0 to 15. It is found that the above-threshold dissociation could be more obviously observed from the TOF spectra when the initial vibrational state is set as v=6 for a moderate-intensity femtosecond laser field.