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arXiv · 2506.17377

Quantum secure direct communication of continuous-time signals using Whittaker Nyquist Shannon theorem

V. F. Guedes·S. T. de Oliveira·G. L. de Oliveira·J. B. R. Silva·R. V. Ramos
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Abstract

In the present work, we provide a new quantum secure direct communication protocol and its experimental implementation. The proposed protocol can be used to transfer, in a secure way, continuous signals, like audio signal, from Alice to Bob. The security is guaranteed by the quantum nature of optical signals and the Whittaker-Nyquist-Shannon theorem. Furthermore, it can be easily implemented with common optical devices that are commercially available.

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V. F. Guedes, S. T. de Oliveira, G. L. de Oliveira, J. B. R. Silva, R. V. Ramos. 2025-06-20. Quantum secure direct communication of continuous-time signals using Whittaker Nyquist Shannon theorem. https://arxiv.org/abs/2506.17377

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