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Phase-dependent interaction in a 4-level atomic configuration

Giovanna Morigi·Sonja Franke-Arnold·Gian-Luca Oppo
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Abstract

We study a four-level atomic scheme interacting with four lasers in a closed-loop configuration with a $\diamondsuit$ (diamond) geometry. We investigate the influence of the laser phases on the steady state. We show that, depending on the phases and the decay characteristic, the system can exhibit a variety of behaviors, including population inversion and complete depletion of an atomic state. We explain the phenomena in terms of multi-photon interference. We compare our results with the phase-dependent phenomena in the double-$Λ$ scheme, as studied in [Korsunsky and Kosachiov, Phys. Rev A {\bf 60}, 4996 (1999)]. This investigation may be useful for developing non-linear optical devices, and for the spectroscopy and laser-cooling of alkali-earth atoms.

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Giovanna Morigi, Sonja Franke-Arnold, Gian-Luca Oppo. 2002-07-16. Phase-dependent interaction in a 4-level atomic configuration. https://doi.org/10.1103/physreva.66.053409

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