Robert R. Jones
Abstract:Essentially all processes within atoms and molecules, as well as the interaction between atoms/molecules and applied fields, depend critically on the relative positions and/or momenta of the particles and their orientation with respect to external fields. Yet in most experiments these key parameters are not well defined, but instead, are distributed over a range of values according to a quantum probability amplitude or statistical ensemble. However, ultra-short laser pulses (or pulse sequences) can be used to create coherent superposition states in which the reactants are localized in specific coordinates at particular times. In Rydberg atoms, the electronic eigenstates serve as the building blocks for creating specific time-dependent structures, i.e. wavepackets, within atoms. The manner in which the wavepacket evolves is determined by which eigenstates are superimposed, and the time scales over which the evolution occurs is determined by the inverse of the energy differences between eigenstates. Recent experiments performed using appropriately designed wavepackets have enabled our investigation of non-perturbative dynamics as a function of the initial values of key parameters such as relative distance, momenta, and/or orientation.
Status: Photonic, Electronic, and Atomic Collisions XXIV, 87 (2006).