Spontaneous emission and atomic line shift in causal perturbation theory

Karl-Peter Marzlin; Bryce Fitzgerald

doi:10.1063/1.5002556

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arXiv · 1801.02224

Spontaneous emission and atomic line shift in causal perturbation theory

Karl-Peter Marzlin·Bryce Fitzgerald

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Abstract

We derive spontaneous emission rate and line shift for two-level atoms coupled to the radiation field using causal perturbation theory. In this approach, employing the theory of distribution splitting prevents the occurrence of divergent integrals. Our method confirms the result for atomic decay rate but suggests that the cutoff frequency for the atomic line shift is determined by the atomic mass, rather than Bohr radius or electron mass.

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Karl-Peter Marzlin, Bryce Fitzgerald. 2018-01-07. Spontaneous emission and atomic line shift in causal perturbation theory. https://doi.org/10.1063/1.5002556

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