Atomic velocity selection by interference in two-photon ionization

J. C. Garreau, D. Wilkowski, D. Hennequin, V. Zehnle

J. Nonlinear Opt. Phys. Mater. 5 911-919 (1996)

This paper discusses a new scheme for generating quantum coherence between different degrees of freedom of an atom interacting with two modes of the electromagnetic field. The presence of quantum interference in a two-photon coupling between the ground state of the atom and the continuum through two quasi-resonant intermediate states induces selective ionization of the atoms for particular combinations of the different parameters characterizing the degrees of freedom of the system, leading to quantum coherence between the internal state, the center-of-mass motion of the atom, and the electromagnetic field. The application of this method to the selection of an atomic velocity class is discussed.