  The laser excitation of an ion crystal to high lying and long-lived
electronic states is a genuine many-body process even if in fact only a single
ion is excited. This is a direct manifestation of the strong coupling between
internal and external dynamics and becomes most apparent in the vicinity of a
structural phase transition. Here we show that utilizing highly excited states
offers a new approach to the coherent manipulation of ion crystals. This
permits the study of phenomena which rely on a strong coupling between
electronic and vibrational dynamics and opens up a route towards the quantum
simulation of molecular processes in a Paul trap.
