Spatiotemporal imaging of ultrafast molecular motion:: Collapse and revival of the D2+ nuclear wave packet

We report on a real-time imaging of the ultrafast D-2(+) rovibrational nuclear wave-packet motion performed using a combination of a pump-probe setup with 7 fs laser pulses and a reaction-microscope spectrometer. We observe fast dephasing (collapse) of the vibrational wave packet and its subsequent revival and prove rotational excitation in ultrashort laser pulses. Channel-selective Fourier analysis of the wave packet's long-term (similar to 3000 fs) evolution allows us to resolve its individual constituents, revealing unique information on the mechanisms of strong-field ionization and dissociation.