title: Coherence-manipulation of an atomic wave packet via electron-electron correlations.
abstract: An electronic wave packet is excited in the Rydberg states of atomic calcium. The strong excitation of the remaining valence electron modifies the particular coherent superposition state associated with this Rydberg wave packet due to the electron-electron correlation. This modification is observed by a coherent pump-probe measurement in which the change of the global phase of the wave packet with respect to a local oscillator is found. The magnitude of the electron-electron correlation is varied experimentally and leads to sharp resonances in the phase. The coherence is maintained despite the open autoionization channel. The process also allows the manipulation of individual states within the wave packet.
authors.forename: X
authors.initials: X
authors.lastname: Chen
authors.forename: J
authors.initials: J
authors.lastname: Yeazell