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arXiv · 1605.02853

Practical decoy-state round-robin differential-phaseshift quantum key distribution

Ying-Ying Zhang·Wan-Su Bao·Chun Zhou·Hong-Wei Li·Yang Wang·Mu-Sheng Jiang
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Abstract

To overcome the signal disturbance from the transmission process, recently, a new type of protocol named round-robin differential-phase-shift(RRDPS) quantum key distribution[Nature 509, 475(2014)] is proposed. It can estimate how much information has leaked to eavesdropper without monitoring bit error rates. In this paper, we compare the performance of RRDPS using different sources without and with decoy-state method, such as weak coherent pulses(WCPs) and heralded single photon source(HSPS). For practical implementations, we propose finite decoy-state method for RRDPS, the performance of which is close to the infinite one. Taking WCPs as an example, the three-intensity decoystate protocol can distribute secret keys over a distance of 128 km when the length of pulses packet is 32, which confirms the great practical interest of our method.

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Ying-Ying Zhang, Wan-Su Bao, Chun Zhou, Hong-Wei Li, Yang Wang, Mu-Sheng Jiang. 2016-05-10. Practical decoy-state round-robin differential-phaseshift quantum key distribution. https://doi.org/10.1364/oe.24.020763

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