By exciting an atom or a molecule from a bound state into a continuum via two, equal-energy optical pathways, it is possible both to control the excitation outcome and to gain insights into properties of the continua, which are not available from conventional photochemistry. Here we focus primarily on the second goal. We combine a detailed experimental study of one- vs three-photon excitation of HI with a general theory of two-pathway excitation to illustrate the potential of such techniques to unravel coupling mechanisms in dissociation and ionization continua, to detect weak spectroscopic transitions, and to determine the phase of quasi-bound eigenstates.
|Journal||COMMENTS ON MODERN PHYSICS|
|State||Published - 2002|