Article révisé par les pairs
| Résumé : | Following a historical introduction on the nature of light and its interaction with matter, a survey is given of the development of lasers capable of delivering short pulses of very intense radiation. The peak intensities of these laser pulses are so high that the corresponding laser fields can compete with, or even dominate, the Coulomb field in governing the dynamics of atomic systems. As a result, new phenomena, known as multiphoton processes, can occur. An outline is given of the basic properties found in the study of three important multiphoton processes. Firstly, the multiphoton ionization of atoms and the phenomenon of"above-threshold ionization". Secondly, the emission by atoms of high-order harmonics of the frequency of the driving laser and their use to generate laser pulses having durations in the attosecond range. Thirdly, laser-assisted electron-atom collisions. A review is then given of the main non-perturbative methods which have been used to perform theoretical studies of multiphoton processes. |
