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Prevent eavesdropping with bright reference pulses for practical quantum key distribution

Guang Wu·Jie Chen·Yao Li·Lilin Xu·Heping Zeng
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Abstract

We analyze the application of bright reference pulses to prevent the photon-number-splitting attack in weak-pulse quantum key distribution. Under the optimal eavesdropping strategy as far as we know, the optimal parameters of bright reference and signal pulses can ensure a secure transmission distance up to 146 km. To realize the quantum key distribution scenario with up-present techniques, we present an experimentally feasible scheme to create a large splitting ratio between bright reference and signal pulses, and to switch the bright reference pulses away from signal pulses to avoid the after-pulse disturbance.

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Guang Wu, Jie Chen, Yao Li, Lilin Xu, Heping Zeng. 2006-09-13. Prevent eavesdropping with bright reference pulses for practical quantum key distribution. https://doi.org/10.1103/physreva.74.062323

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