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Secure direct bidirectional communication protocol using the Einstein-Podolsky-Rosen pair block

Z. J. Zhang·Z. X. Man
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Abstract

In light of Deng-Long-Liu's two-step secret direct communication protocol using the Einstein-Podolsky-Rosen pair block [Phys. Rev. A {\bf 68}, 042317 (2003)], by introducing additional local operations for encoding, we propose a brand-new secure direct communication protocol, in which two legitimate users can simultaneously transmit their different secret messages to each other in a set of quantum communication device.

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Z. J. Zhang, Z. X. Man. 2004-03-30. Secure direct bidirectional communication protocol using the Einstein-Podolsky-Rosen pair block. https://arxiv.org/abs/quant-ph/0403215

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