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arXiv · 2610.40358

Quantum communication: a discrimination approach

Hao-Chung Cheng
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Abstract

We develop a state discrimination approach to unassisted quantum communication through a noisy quantum channel. Starting from the operational duality between entanglement recovery and state discrimination, we construct entanglement-generation codes with explicit decoders constructed from Petz recovery maps. The resulting error bounds hold for every number of channel uses and are expressed in terms of Petz-Rényi coherent information. For product sources, they yield exponential error decay at rates below coherent information.

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Hao-Chung Cheng. 2026-10-29. Quantum communication: a discrimination approach. https://arxiv.org/abs/2610.40358

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