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arXiv · 1001.1704

Quantum communication with photon-number entangled states and realistic photodetection

Vladyslav C. Usenko·Matteo G. A. Paris
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Abstract

We address the effects of realistic photodetection, with nonunit quantum efficiency and background noise (dark counts), on the performances of quantum communication schemes based on photon-number entangled states. We consider channels based on Gaussian twin-beam states and non-Gaussian two-mode coherent states and evaluate the channel capacity by optimizing the bit discrimination threshold. We found that TWB-based channels are more robust against noise than TMC-based ones and that this result is almost independent on the statistics of dark counts.

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Vladyslav C. Usenko, Matteo G. A. Paris. 2010-01-11. Quantum communication with photon-number entangled states and realistic photodetection. https://doi.org/10.1016/j.physleta.2010.01.016

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