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arXiv · 1503.01730

Exact theory and numeric results for short pulse ionization of simple model atom in one dimension

Abstract

Our exact theory for continuous harmonic perturbation of a one dimensional model atom by parametric variations of its potential is generalized for the cases when a) the atom is exposed to short pulses of an external harmonic electric field and b) the forcing is represented by short bursts of different shape changing the strength of the binding potential. This work is motivated not only by the wide use of laser pulses for atomic ionization, but also by our earlier study of the same model which successfully described the ionization dynamics in all orders, i.e. the multi-photon processes, though being treated by the non-relativistic Schrödinger equation. In particular, it was shown that the bound atom cannot survive the excitation of its potential caused by any non-zero frequency and amplitude of the continuous harmonic forcing. Our present analysis found important laws of the atomic ionization by short pulses, in particular the efficiency of ionizing this model system and presumably real ones as well.

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Alexander Rokhlenko. 2015-03-05. Exact theory and numeric results for short pulse ionization of simple model atom in one dimension. https://doi.org/10.1063/1.4964615

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