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arXiv · 2009.12535

Double C-NOT attack on a single-state semi-quantum key distribution protocol and its improvement

Jun Gu·Tzonelih Hwang
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Abstract

Recently, Zhang et al. proposed a single-state semi-quantum key distribution protocol (Int. J. Quantum Inf, 18, 4, 2020) to help a quantum participant to share a secret key with a classical participant. However, this study shows that an eavesdropper can use a double C-NOT attack to obtain parts of the final shared key without being detected by the participants. To avoid this problem, a modification is proposed here.

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Jun Gu, Tzonelih Hwang. 2020-09-26. Double C-NOT attack on a single-state semi-quantum key distribution protocol and its improvement. https://arxiv.org/abs/2009.12535

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