Identification Over Quantum Broadcast Channels

Johannes Rosenberger; Christian Deppe; Uzi Pereg

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arXiv · 2201.11056

Identification Over Quantum Broadcast Channels

Johannes Rosenberger·Christian Deppe·Uzi Pereg

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Abstract

Identification over quantum broadcast channels is considered. As opposed to the information transmission task, the decoder only identifies whether a message of his choosing was sent or not. This relaxation allows for a double-exponential code size. An achievable identification region is derived for a quantum broadcast channel, and a full characterization for the class of classical-quantum broadcast channels. The identification capacity region of the single-mode pure-loss bosonic broadcast channel is obtained as a consequence. Furthermore, the results are demonstrated for the quantum erasure broadcast channel, where our region is suboptimal, but improves on the best previously known bounds.

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Johannes Rosenberger, Christian Deppe, Uzi Pereg. 2022-01-26. Identification Over Quantum Broadcast Channels. https://arxiv.org/abs/2201.11056

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