Non-perturbative Methods Applied to Multiphoton Ionization
نویسندگان
چکیده
We discuss the use of non-perturbative methods in the treatment of atomic ionization. Particular attention is given to schemes of the type proposed by Keldysh where multiphoton ionization and tunnel auto-ionization occur for high intensity fields. These methods are shown to correspond to a certain type of expansion of the T-matrix in the intra-atomic potential, in this manner a criterium concerning the range of application of these non-perturbative scheme is suggested. A brief comparison between the ionization rate of atoms in the presence of linearly and circularly polarized light is presented.
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