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Spontaneous emission and lifetime modification caused by an intense electromagnetic field

P. Facchi·S. Pascazio
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Abstract

We study the temporal evolution of a three-level system (such as an atom or a molecule), initially prepared in an excited state, bathed in a laser field tuned at the transition frequency of the other level. The features of the spontaneous emission are investigated and the lifetime of the initial state is evaluated: a Fermi "golden rule" still applies, but the on-shell matrix elements depend on the intensity of the laser field. In general, the lifetime is a decreasing function of the laser intensity. The phenomenon we discuss can be viewed as an "inverse" quantum Zeno effect and can be analyzed in terms of dressed states.

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P. Facchi, S. Pascazio. 2000-03-28. Spontaneous emission and lifetime modification caused by an intense electromagnetic field. https://doi.org/10.1103/physreva.62.023804

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