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arXiv · 2503.21002

Covert Entanglement Generation and Secrecy

Ohad Kimelfeld·Boulat A. Bash·Uzi Pereg
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Abstract

We determine the covert capacity for entanglement generation over a noisy quantum channel. While secrecy guarantees that the transmitted information remains inaccessible to an adversary, covert communication ensures that the transmission itself remains undetectable. The entanglement dimension follows a square root law (SRL) in the covert setting, i.e., $O(\sqrt{n})$ Einstein-Podolsky-Rosen (EPR) pairs can be distributed covertly and reliably over $n$ channel uses. We begin with covert communication of classical information under a secrecy constraint. We then leverage this result to construct a coding scheme for covert entanglement generation. Single-letter expressions are derived for the covert key-assisted and unassisted secrecy capacities, as well as for the covert entanglement-generation capacity.

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Ohad Kimelfeld, Boulat A. Bash, Uzi Pereg. 2025-03-26. Covert Entanglement Generation and Secrecy. https://doi.org/10.1109/tit.2026.3689208

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