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Quantum coherence and population trapping in three-photon processes

Caroline Champenois·Giovanna Morigi·Juergen Eschner
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Abstract

The spectroscopic properties of a single, tightly trapped atom are studied, when the electronic levels are coupled by three laser fields in an $N$-shaped configuration of levels, whereby a $\Lambda$-type level system is weakly coupled to a metastable state. We show that depending on the laser frequencies the response can be tuned from coherent population trapping at two-photon resonance to novel behaviour at three photon resonance, where the metastable state can get almost unit occupation in a wide range of parameters. For certain parameter regimes the system switches spontaneously between dissipative and coherent dynamics over long time scales.

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Caroline Champenois, Giovanna Morigi, Juergen Eschner. 2006-07-30. Quantum coherence and population trapping in three-photon processes. https://doi.org/10.1103/physreva.74.053404

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