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arXiv · 1209.4304

Two-step orthogonal-state-based protocol of quantum secure direct communication with the help of order-rearrangement technique

Preeti Yadav·R. Srikanth·Anirban Pathak
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Abstract

The Goldenberg-Vaidman (GV) protocol for quantum key distribution (QKD) uses orthogonal encoding states of a particle. Its security arises because operations accessible to Eve are insufficient to distinguish the two states encoding the secret bit. We propose a two-particle cryptographic protocol for quantum secure direct communication, wherein orthogonal states encode the secret, and security arises from restricting Eve from accessing any two-particle operations. However, there is a non-trivial difference between the two cases. While the encoding states are perfectly indistinguishable in GV, they are partially distinguishable in the bi-partite case, leading to a qualitatively different kind of information-vs-disturbance trade-off and also options for Eve in the two cases.

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Preeti Yadav, R. Srikanth, Anirban Pathak. 2012-09-19. Two-step orthogonal-state-based protocol of quantum secure direct communication with the help of order-rearrangement technique. https://doi.org/10.1007/s11128-014-0825-8

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