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Secure communication using coherent states

Geraldo A. Barbosa·Eric Corndorf·Prem Kumar·Horace P. Yuen·G. Mauro D'Ariano·Matteo G. A. Paris·Paolo Perinotti
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Abstract

We demonstrate that secure communication using coherent states is possible. The optimal eavesdropping strategy for an M-ry ciphering scheme shows that the minimum probability of error in a measurement for bit determination can be made arbitrarily close to the pure guessing value P_e=1/2. This ciphering scheme can be optically amplified without degrading the security level. New avenues are open to secure communications at high speeds in fiber-optic or free-space channels.

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Geraldo A. Barbosa, Eric Corndorf, Prem Kumar, Horace P. Yuen, G. Mauro D'Ariano, Matteo G. A. Paris, Paolo Perinotti. 2003-07-28. Secure communication using coherent states. https://arxiv.org/abs/quant-ph/0210089

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