Complete view of Stark wave-packet evolution

Picosecond laser pulses have been used to produce Rydberg wave packets in c alcium atoms in the presence of a strong static electric field. The dynamic s of the Stark wave packets have been observed by measuring the momentum-sp ace probability distribution as a function of time. The full precession of the electronic orbital angular momentum, the appearance of a large-amplitud e, linear oscillation of the electronic dipole moment, and a pronounced, pe riodic up-down asymmetry in the momentum distribution are all observed dire ctly. [S1050-2947(99)50406-X].