Ionization
Quasi-static tunnel ionization

The quasi-static tunneling (QST) is the ionization whose rate can be satisfactorily predicted by the ADK model, i.e. the limit of the PPT model when γ {\displaystyle \gamma } approaches zero. The rate of QST is given by

As compared to W P P T {\displaystyle W_{PPT}} the absence of summation over n, which represent different above threshold ionization (ATI) peaks, is remarkable.
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