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Secure Direct Communication with a Quantum One-Time-Pad

Fu-Guo Deng·Gui Lu Long
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Abstract

Quantum secure direct communication is the direct communication of secret messages without first producing a shared secret key. It maybe used in some urgent circumstances. Here we propose a quantum secure direct communication protocol using single photons. The protocol uses batches of single photons prepared randomly in one of four different states. These single photons serve as a one-time-pad which are used directly to encode the secret messages in one communication process. We also show that it is unconditionally secure. The protocol is feasible with present-day technique.

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Fu-Guo Deng, Gui Lu Long. 2004-05-28. Secure Direct Communication with a Quantum One-Time-Pad. https://doi.org/10.1103/physreva.69.052319

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