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arXiv · 1203.3396

Heralded photon amplification for quantum communication

C. I. Osorio·N. Bruno·N. Sangouard·H. Zbinden·N. Gisin·R. T. Thew
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Abstract

Heralded noiseless amplification based on single-photon sources and linear optics is ideally suited for long-distance quantum communication tasks based on discrete variables. We experimentally demonstrate such an amplifier, operating at telecommunication wavelengths. Coherent amplification is performed with a gain of G=1.98+/-0.2, for a state with a maximum expected gain G=2. We also demonstrate that there is no need for a stable phase reference between the initial signal state and the local auxiliary photons used by the amplifier. These results highlight the potential of heralded quantum amplifiers for long-distance quantum communication, and bring device-independent quantum key distribution one step closer.

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C. I. Osorio, N. Bruno, N. Sangouard, H. Zbinden, N. Gisin, R. T. Thew. 2012-03-16. Heralded photon amplification for quantum communication. https://doi.org/10.1103/physreva.86.023815

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