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Ionization of a Model Atom: Exact Results and Connection with Experiment

Ovidiu Costin·Joel L. Lebowitz·Alexander Rokhlenko
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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 $ω$. The survival probability is for small $r$ given by $e^{-Γt}$ for times of order $Γ^{-1} \sim r^{-2n}$, where $n$ is the number of ``photons'' required for ionization, with enhanced stability at resonances. For late times the decay is like $t^{-3}$. Results are for a 1d system with a delta function potential of strength $-g(1 + η(t))$ but comparison with experiments on the microwave ionization of excited hydrogen atoms and with recent analytical work indicate that many features are universal.

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Ovidiu Costin, Joel L. Lebowitz, Alexander Rokhlenko. 1999-05-18. Ionization of a Model Atom: Exact Results and Connection with Experiment. https://arxiv.org/abs/physics/9905038

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