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Exact Results for the Ionization of a Model Quantum System

O. Costin·A. Rokhlenko·J. Lebowitz
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Abstract

We prove that a model atom having one bound state will be fully ionized by a time periodic potential of arbitrary strength r and frequency omega. Starting with the system in the bound state, the survival probability is for small r given by exp(-Gamma t) for times of order GAMMA^(-1)~r^(-2n) where n is the minimum number of 'photons' required for ionization (with large modifications at resonances). For late times the decay is as t^(-3) with the power law modulated by oscillations. As r increases, the time over which there is exponential decay becomes shorter and the power law behaviour starts earlier. Results are for a parametrically excited one-dimensional system with zero-range potential but comparison with analyticalworks and with experiments indicates that many features are general.

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O. Costin, A. Rokhlenko, J. Lebowitz. 2006-08-16. Exact Results for the Ionization of a Model Quantum System. https://arxiv.org/abs/math-ph/0608039

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