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Quantum Memory Based on $Λ$-Atoms Ensemble with Two-Photon Resonance EIT

Y. Li·C. P. Sun
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Abstract

We study the $Λ$-atoms ensemble based quantum memory for the storage of the quantum information carried by a probe light field. Two atomic Rabi transitions of the ensemble are coupled to the quantum probe field and classical control field respectively with a same detuning. Making use of the hidden symmetry analysis developed recently for the on-resonance EIT case (Sun, Li, and Liu, Phys. Rev. Lett. 91, 147903 (2003)), we show that the dark states and dark-state polaritons can still exist for the case of two-photon resonance EIT. Starting from these dark states we construct a complete class of eigen-states of the total system. A explicit form of the adiabatic condition is also given in order to achieve the memory and retrieve of quantum information.

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Y. Li, C. P. Sun. 2004-02-24. Quantum Memory Based on $Λ$-Atoms Ensemble with Two-Photon Resonance EIT. https://doi.org/10.1140/epjd%2Fe2004-00097-y

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