  Coherent light pulses of few to hundreds of femtoseconds (fs) duration have
prolifically served the field of ultrafast phenomena. While fs pulses address
mainly dynamics of nuclear motion in molecules or lattices in the gas, liquid
or condensed matter phase, the advent of attosecond pulses has in recent years
provided direct experimental access to ultrafast electron dynamics. However,
there are processes involving nuclear motion in molecules and in particular
coupled electronic and nuclear motion that possess few fs or even sub-fs
dynamics. In the present work we have succeeded in addressing simultaneously
vibrational and electronic dynamics in molecular Hydrogen. Utilizing a
broadband extreme-ultraviolet (XUV) continuum the entire, Frank-Condon allowed
spectrum of H2 is coherently excited. Vibrational, electronic and ionization
1fs scale dynamics are subsequently tracked by means of XUV-pump-XUV-probe
measurements. These reflect the intrinsic molecular behavior as the XUV probe
pulse hardly distorts the molecular potential.
