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Quantum secure communication scheme with W state

Jian Wang·Quan Zhang·Chao-jing Tang
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Abstract

Recently, Cao et al. proposed a new quantum secure direct communication scheme using W state. In their scheme, the error rate introduced by an eavesdropper who takes intercept-resend attack, is only 8.3%. Actually, their scheme is just a quantum key distribution scheme because the communication parties first create a shared key and then encrypt the secret message using one-time pad. We then present a quantum secure communication scheme using three-qubit W state. In our scheme, the error rate is raised to 25% and it is not necessary for the present scheme to use alternative measurement or Bell basis measurement. We also show our scheme is unconditionally secure.

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Jian Wang, Quan Zhang, Chao-jing Tang. 2006-03-16. Quantum secure communication scheme with W state. https://doi.org/10.1088/0253-6102%2F48%2F4%2F013

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