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Beamsplitting attack to the revised KKKP protocol and a possible solution

Xiang-Bin Wang·Qiang Zhang·Yu-Ao Chen·Wong-Young Hwang·Myungshik Kim·Jian-Wei Pan
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Abstract

We show that the revised KKKP protocol proposed by Kye and Kim [Phys. Rev. Lett. 95,040501(2005)] is still insecure with coherent states by a type of beamsplitting attack. We then further revise the KKKP protocol so that it is secure under such type of beamsplitting attack. The revised scheme can be used for not-so-weak coherent state quantum key distribution.

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Xiang-Bin Wang, Qiang Zhang, Yu-Ao Chen, Wong-Young Hwang, Myungshik Kim, Jian-Wei Pan. 2006-03-15. Beamsplitting attack to the revised KKKP protocol and a possible solution. https://arxiv.org/abs/quant-ph/0603010

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