Rydberg wave packets in many-electron atoms excited by short laser pulses.

Abstract

An atomic electron excited to a coherent superposition of Rydberg states by a short laser pulse corresponds to a wave packet moving on a radial Kepler orbit. The dynamics of the motion of the wave packet can be observed in a two-photon process where a first laser pulse excites the wave packet, which at a later time is probed by a second pulse. In a many-electron atom a single valence electron excited to the Rydberg wave packet can exchange energy with the atomic ion core (electron correlation), whenever the Rydberg wave packet passes through the atomic core region. We can view this orbiting of the wave packet as a succession of below-threshold inelastic scattering events from the atomic ion core. A theory of two-photon absorption with time-delayed short laser pulses is developed which is based on a ``smooth'' multichannel quantum-defect Green function.