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Narrow Spectral Feature In Resonance Fluorescence With A Single Monochromatic Laser Field

Joerg Evers·Christoph H. Keitel
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Abstract

We describe the resonance fluorescence spectrum of an atomic three-level system where two of the states are coupled by a single monochromatic laser field. The influence of the third energy level, which interacts with the two laser-coupled states only via radiative decays, is studied in detail. For a suitable choice of parameters, this system gives rise to a very narrow structure at the laser frequency in the fluorescence spectrum which is not present in the spectrum of a two-level atom. We find those parameter ranges by a numerical analysis and use the results to derive analytical expressions for the additional narrow peak. We also derive an exact expression for the peak intensity under the assumption that a random telegraph model is applicable to the system. This model and a simple spring model are then used to describe the physical origins of the additional peak. Using these results, we explain the connection between our system, a three-level system in V-configuration where both transitions are laser driven, and a related experiment which was recently reported.

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Joerg Evers, Christoph H. Keitel. 2002-02-22. Narrow Spectral Feature In Resonance Fluorescence With A Single Monochromatic Laser Field. https://doi.org/10.1103/physreva.65.033813

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