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Quantum relays and noise suppression using linear optics

B. C. Jacobs·T. B. Pittman·J. D. Franson
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Abstract

Probabilistic quantum non-demolition (QND) measurements can be performed using linear optics and post-selection. Here we show how QND devices of this kind can be used in a straightforward way to implement a quantum relay, which is capable of extending the range of a quantum cryptography system by suppressing the effects of detector noise. Unlike a quantum repeater, a quantum relay system does not require entanglement purification or the ability to store photons.

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B. C. Jacobs, T. B. Pittman, J. D. Franson. 2002-05-03. Quantum relays and noise suppression using linear optics. https://doi.org/10.1103/physreva.66.052307

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