Final-state interactions in multiphoton-ionization theory
- 1 July 1984
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review A
- Vol. 30 (1) , 245-255
- https://doi.org/10.1103/physreva.30.245
Abstract
In the final state of a multiphoton-ionization process the ejected electron may interact simultaneously with the external laser field and with the residual atomic system. A procedure for calculating transition probabilities for such processes is described which incorporates the effects of resonances in the final continuum states of the atom. By using standard methods of scattering theory, it is shown how these resonant states may be separated out leaving a "background" amplitude which is a smooth function of the energy, and which therefore lends itself more readily to numerical evaluation. Such an evaluation may be based on the generalized Lippmann-Schwinger integral equation presented here. The constraint imposed by unitarity on the background amplitude is derived, and it is pointed out how approximations may be set up which satisfy unitarity automatically. A simplified model is described in order to illustrate this and other features of the theory and to make contact with some earlier work on this subject. Finally, a low-frequency approximation is developed in which final-state interaction effects are accounted for in a relatively simple analytical form.Keywords
This publication has 17 references indexed in Scilit:
- Projection-operator approach to potential scatteringPhysical Review A, 1983
- Electron scattering from a potential in a radiation fieldPhysical Review A, 1983
- Fluorescence induced by resonant multiphoton ionisation near an autoionising stateJournal of Physics B: Atomic and Molecular Physics, 1982
- Multiphoton above-threshold ionisation of xenon at 0.53 and 1.06 mJournal of Physics B: Atomic and Molecular Physics, 1982
- Influence of Spontaneous Emission on Laser-Induced AutoionizationPhysical Review Letters, 1982
- Confluence of Bound-Free Coherences in Laser-Induced AutoionizationPhysical Review Letters, 1981
- Autoionizing states in strong laser fieldsPhysical Review A, 1981
- Interference between radiative emission and autoionization in the decay of excited states of atomsPhysical Review A, 1978
- Continuum level-shift effects in the theory of multiphoton transitionsPhysical Review A, 1978
- Single-particle resonances in the unified theory of nuclear reactionsPhysics Letters B, 1970