Molecular Physics

A perturbative formalism for the spontaneous emission by excited systems

Paolo Grigolini A

Published Jun 1, 1976• 30 citations

Abstract

In this paper we improve a theory that we have previously developed in order to deal with the spontaneous decay of excited systems. These improvements allows us to eliminate some unpleasant features of the previous approach as well as to study the decay of excited systems in the presence of external irradiation fields and the response of matter to electromagnetic excitations. The present approach allows for a quantitative evaluation of the irradiation field influence on the state lifetimes, which (when the interaction under study is endowed with a ‘strong memory’) is shown to be noticeable even in the cases where the irradiation intensity is small with respect to the unperturbed linewidth. We expect that, taking into account also the third-order perturbation contributions, here disregarded, the slow-motion lineshape problem will be effectively treated by the present approach even in the saturation regime.

DOI: 10.1080/00268977600101381

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