ATOMIC VELOCITY SELECTION BY INTERFERENCE IN 2-PHOTON IONIZATION

This paper discusses a new scheme for generating quantum coherence bet ween different degrees of freedom of an atom interacting with two mode s of the electromagnetic field. The presence of quantum interference i n a two-photon coupling between the ground state of the atom and the c ontinuum through two quasi-resonant intermediate states induces select ive ionization of the atoms for particular combinations of the differe nt parameters characterizing the degrees of freedom of the system, lea ding to quantum coherence between the internal state, the center-of-ma ss motion of the atom, and the electromagnetic field. The application of this method to the selection of an atomic velocity class is discuss ed.