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arXiv · 1002.4068

Multiplexed communication over a high-speed quantum channel

M. Heurs·J. G. Webb·A. E. Dunlop·C. C. Harb·T. C. Ralph·E. H. Huntington
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Abstract

In quantum information systems it is of particular interest to consider the best way in which to use the non-classical resources consumed by that system. Quantum communication protocols are integral to quantum information systems and are amongst the most promising near-term applications of quantum information science. Here we show that a multiplexed, digital quantum communications system supported by comb of vacuum squeezing has a greater channel capacity per photon than a source of broadband squeezing with the same analogue bandwidth. We report on the time-resolved, simultaneous observation of the first dozen teeth in a 2.4 GHz comb of vacuum squeezing produced by a sub-threshold OPO, as required for such a quantum communications channel. We also demonstrate multiplexed communication on that channel.

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M. Heurs, J. G. Webb, A. E. Dunlop, C. C. Harb, T. C. Ralph, E. H. Huntington. 2010-02-22. Multiplexed communication over a high-speed quantum channel. https://doi.org/10.1103/physreva.81.032325

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