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Quantum telecommunication based on atomic cascade transitions

T. Chaneliere·D. N. Matsukevich·S. D. Jenkins·T. A. B. Kennedy·M. S. Chapman·A. Kuzmich
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Abstract

A quantum repeater at telecommunications wavelengths with long-lived atomic memory is proposed, and its critical elements are experimentally demonstrated using a cold atomic ensemble. Via atomic cascade emission, an entangled pair of 1530 nm and 780 nm photons is generated. The former is ideal for long-distance quantum communication, and the latter is naturally suited for mapping to a long-lived atomic memory. Together with our previous demonstration of photonic-to-atomic qubit conversion, both of the essential elements for the proposed telecommunications quantum repeater have now been realized.

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T. Chaneliere, D. N. Matsukevich, S. D. Jenkins, T. A. B. Kennedy, M. S. Chapman, A. Kuzmich. 2006-01-10. Quantum telecommunication based on atomic cascade transitions. https://doi.org/10.1103/physrevlett.96.093604

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