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arXiv · 1506.00518

An entangled-LED driven quantum relay over 1 km

C. Varnava·R. M. Stevenson·J. Nilsson·J. Skiba-Szymanska·B. Dzurňák·M. Lucamarini·R. V. Penty·I. Farrer·D. A. Ritchie·A. J. Shields
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Abstract

Quantum cryptography allows confidential information to be communicated between two parties, with secrecy guaranteed by the laws of nature alone. However, upholding guaranteed secrecy over quantum communication networks poses a further challenge, as classical receive-and-resend routing nodes can only be used conditional of trust by the communicating parties. Here, we demonstrate the operation of a quantum relay over 1 km of optical fiber, which teleports a sequence of photonic quantum bits to a receiver by utilizing entangled photons emitted by a semiconductor LED. The average relay fidelity of the link is 0.90+/-0.03, exceeding the classical bound of 0.75 for the set of states used, and sufficiently high to allow error correction. The fundamentally low multi-photon emission statistics and the integration potential of the source present an appealing platform for future quantum networks.

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C. Varnava, R. M. Stevenson, J. Nilsson, J. Skiba-Szymanska, B. Dzurňák, M. Lucamarini, R. V. Penty, I. Farrer, D. A. Ritchie, A. J. Shields. 2015-06-03. An entangled-LED driven quantum relay over 1 km. https://doi.org/10.1038/npjqi.2016.6

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