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Efficient quantum key distribution scheme with nonmaximally entangled states

Peng Xue·Chuan-Feng Li·Guang-Can Guo
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Abstract

We propose an efficient quantum key distribution scheme based on entanglement. The sender chooses pairs of photons in one of the two equivalent nonmaximally entangled states randomly, and sends a sequence of photons from each pair to the receiver. They choose from the various bases independently but with substantially different probabilities, thus reducing the fraction of discarded data, and a significant gain in efficiency is achieved. We then show that such a refined data analysis guarantees the security of our scheme against a biased eavesdropping strategy.

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Peng Xue, Chuan-Feng Li, Guang-Can Guo. 2001-01-11. Efficient quantum key distribution scheme with nonmaximally entangled states. https://doi.org/10.1103/physreva.64.032305

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