Nonadiabatic alignment of van der Waals--force-bound argon dimers by femtosecond laser pulses

Abstract

We demonstrated that the weak van der Waals--force-bound argon dimer can be nonadiabatically aligned by nonresonant femtosecond laser pulses, showing periodic alignment and anti-alignment revivals after the extinction of the laser pulse. Based on the measured nonadiabatic alignment trace, the rotational constant of the argon dimer ground state is determined to be ${B}_{0}=$ 0.05756 \ifmmode\pm\else\textpm\fi{} 0.00004 cm${}^{\ensuremath{-}1}$. Noticeable alignment dependence of frustrated tunneling ionization and bond-softening induced dissociation of the argon dimer are observed.