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arXiv · 1507.00978

Modified atomic decay rate near absorptive scatterers at finite temperature

L. G. Suttorp·A. J. van Wonderen
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Abstract

The change in the decay rate of an excited atom that is brought about by extinction and thermal-radiation effects in a nearby dielectric medium is determined from a quantummechanical model. The medium is a collection of randomly distributed thermally-excited spherical scatterers with absorptive properties. The modification of the decay rate is described by a set of correction functions for which analytical expressions are obtained as sums over contributions from the multipole moments of the scatterers. The results for the modified decay rate as a function of the distance between the excited atom and the dielectric medium show the influence of absorption, scattering and thermal-radiation processes. Some of these processes are found to be mutually counteractive. The changes in the decay rate are compared to those following from an effective-medium theory in which the discrete scatterers are replaced by a continuum.

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L. G. Suttorp, A. J. van Wonderen. 2015-07-03. Modified atomic decay rate near absorptive scatterers at finite temperature. https://doi.org/10.1103/physreva.92.013843

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