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arXiv · 1011.2110

Efficient Phase-Encoding Quantum Key Generation with Narrow-Band Single Photons

Hui Yan·Shi-Liang Zhu·Shengwang Du
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Abstract

We propose an efficient phase-encoding quantum secret key generation scheme with heralded narrow-band single photons. The key information is carried by the phase modulation directly on the single-photon temporal waveform without using any passive beam splitters or optical switches. We show that, when the technique is applied to the conventional fiber-based phase-encoding BB84 and differential phase shift (DPS) quantum key distribution schemes, the key generation efficiencies can be improved by a factor of 2 and 3, respectively. For N(>3)-period DPS systems, the key generation efficiency can be improved by a factor of N. The technique is suitable for quantum memory-based long-distance fiber communication system.

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Hui Yan, Shi-Liang Zhu, Shengwang Du. 2011-05-29. Efficient Phase-Encoding Quantum Key Generation with Narrow-Band Single Photons. https://doi.org/10.1088/0256-307x%2F28%2F7%2F070307

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