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Stability of excited atoms in small cavities

G. Flores-Hidalgo·A. P. C. Malbouisson·Y. W. Milla
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Abstract

We consider a system consisting of an atom in the approximation of a harmonic oscillator of frequency $\barω$, coupled to the scalar potential inside a spherical reflecting cavity of radius R. We use {\it dressed} states introduced in a previous publication [Andion, Malbouisson and Matos Neto, J. Phys. A34, 3735 (2001)], which allow a non-perturbative unified description of the atom radiation process, in both cases, of a finite or an arbitrarily large cavity. We perform a study of the energy distribution in a small cavity, with the initial condition that the atom is in the first excited state and we conclude for the quasi-stability of the excited atom. For instance, for a frequency $\barω$ of the order $\barω\sim 4.00\times 10^{14}/s$ (in the visible red), starting from the initial condition that the atom is in the first excited level, we find that for a cavity with diameter $2R\sim 1.0\times 10^{-6}m$, the probability that the atom be at any time still in the first excited level, will be of the order of 97%. For a typical microwave frequency $\barω\sim 2,00\times 10^{10}/s$ we find stability in the first excited state also of the order of 97% for a cavity radius $R\sim 1.4\times 10^{-2}m$.

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G. Flores-Hidalgo, A. P. C. Malbouisson, Y. W. Milla. 2002-08-12. Stability of excited atoms in small cavities. https://doi.org/10.1103/physreva.65.063414

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