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arXiv · 2506.09474

Covert Entanglement Generation over Bosonic Channels

Evan J. D. Anderson·Michael S. Bullock·Ohad Kimelfeld·Christopher K. Eyre·Filip Rozpędek·Uzi Pereg·Boulat A. Bash
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Abstract

We explore covert entanglement generation over the lossy thermal-noise bosonic channel, which is a quantum-mechanical model of many practical settings, including optical, microwave, and radio-frequency (RF) channels. Covert communication ensures that an adversary is unable to detect the presence of transmissions, which are concealed in channel noise. We show that a square root law (SRL) for covert entanglement generation similar to that for classical communication: $L_{\rm EG}\sqrt{n}$ entangled bits (ebits) can be generated covertly and reliably over $n$ uses of a bosonic channel. We report a single-letter expression for optimal $L_{\rm EG}$ as well as an achievable method. We additionally analyze the performance of covert entanglement generation using single- and dual-rail photonic qubits, which may be more practical for physical implementation.

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Evan J. D. Anderson, Michael S. Bullock, Ohad Kimelfeld, Christopher K. Eyre, Filip Rozpędek, Uzi Pereg, Boulat A. Bash. 2025-06-11. Covert Entanglement Generation over Bosonic Channels. https://arxiv.org/abs/2506.09474

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