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Spin-Squeezing and Light Entanglement in Coherent Population Trapping

Aurelien Dantan·Jean Cviklinski·Elisabeth Giacobino·Michel Pinard
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Abstract

We show that high squeezing and entanglement can be generated at the output of a cavity containing atoms interacting with two fields in a Coherent Population Trapping situation, on account of a non-linear Faraday effect experienced by the fields close to a dark-state resonance in a cavity. Moreover, the cavity provides a feedback mechanism allowing to reduce the quantum fluctuations of the ground state spin, resulting in strong steady state spin-squeezing.

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Aurelien Dantan, Jean Cviklinski, Elisabeth Giacobino, Michel Pinard. 2006-03-22. Spin-Squeezing and Light Entanglement in Coherent Population Trapping. https://doi.org/10.1103/physrevlett.97.023605

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