H$_2^+$ dissociation fragments alignment after few-cycle pulse at mid-infrared regime

By solving the time-dependent Schr\"odinger equation for H$_2^+$ numerically including nuclear rotation for H$_2^+$, we systematically analyzed the H$_2^+$ rotational dynamics after a few-cycle laser pulse for wavelengths in the range 800-2000~nm. This study extends our test of the axial recoil approximation reported in [1] to longer wavelengths. Individual initial vibrational states show different rotational behavior. Generally, dissociation fragments from lower vibrational states tend to anti-align along the laser polarization direction, while the fragments from higher initial states tend to align along the polarization direction. In addition, we found that the carrier-envelope phase does not influence the post-pulse rotation substantially even for the few-cycle pulse. \\[4pt] [1] F. Anis, T. Cackowski, and B. D. Esry, J. Phys. B 42, 091001 (2009)