Alignment-dependent strong field ionization of molecules

We demonstrate a method to measure strong field laser ionization of aligned molecules. The method employs a macroscopic field-free dynamic alignment, which occurs during revivals of rotational wave packets produced by a femtosecond laser pulse. We investigate the dependence of strong field ionization of N-2 on molecular orientation. We determine that N-2 molecules are four times more likely to ionize when aligned parallel to the field than when aligned perpendicular to it.