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arXiv · 1110.3478

Coherent control of collective atom phase for ultralong, inversion-free photon echoes

B. S. Ham
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Abstract

To overcome fundamental limitations of the πoptical pulse-induced population inversion and optical decay-caused short storage time in conventional photon echoes, a coherent control of collective atoms is studied for inversion-free, optical decay-halted photon echoes, where the constraint of photon storage time is now replaced by a spin population decay process. Using phase-controlled double rephasing, an inversion-free photon echo scheme is obtained, where no spontaneous or stimulated emission-driven quantum noise exists. Thus, the present method can be applied for ultralong quantum memories in quantum repeaters for long-distance quantum communications.

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B. S. Ham. 2011-10-16. Coherent control of collective atom phase for ultralong, inversion-free photon echoes. https://doi.org/10.1103/physreva.85.031402

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