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Threshold quantum cryptograph based on Grover's algorithm

Jian-Zhong Du·Su-Juan Qin·Qiao-Yan Wen·Fu-Chen Zhu
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Abstract

Grover's operator in the two-qubit case can transform a basis into its conjugated basis. A permutation operator can transform a state in the two conjugated bases into its orthogonal state. These properties are included in a threshold quantum protocol. The proposed threshold quantum protocol is secure based the proof that the legitimate participators can only eavesdrop 2 bits of 3 bits operation information on one two-qubit with error probability 3/8. We propose a scheme to detect the Trojan horse attack without destroying the legal qubit.

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Jian-Zhong Du, Su-Juan Qin, Qiao-Yan Wen, Fu-Chen Zhu. 2006-06-27. Threshold quantum cryptograph based on Grover's algorithm. https://doi.org/10.1016/j.physleta.2006.11.024

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