Fermi's Golden Rule (FGR) states that the ionization rate of an atom increases proportionally to the light intensity, provide that ionization with a single photon is possible. Pont and Gavrila were the first to show that at high intensities this relation breaks down in a counter-intuitive way: the ionization rate of the atom decreases dramatically with intensity above a certain critical intensity Icr. This effect has become known as stabilization. To date there have been proposed a number of physically distinct mechanisms that are collectively known as stabilization. They all have in common that a fraction of the atoms retains its electrons after exposure to a laser pulse, even if the amplitude or duration of the pulse is increased further.

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D.K. Evans , S.L. Chin

Muller, H. G., & de Boer, M. P. (1994). Stabilization: The experiment. In D. K. Evans & S. L. Chin (Eds.), Multiphoton Processes : Proceedings of the 6th International Conference, Universite Laval, Ste. Foy, Quebec, Canada, 25-30 June 1993 (pp. 417–422).