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arXiv · 2311.13945

Quantum network-entanglement measures

Zhen-Peng Xu·Julio I. de Vicente·Liang-Liang Sun·Sixia Yu
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Abstract

Quantum networks are of high interest nowadays and a quantum internet has been long envisioned. Network-entanglement adapts the notion of entanglement to the network scenario and network-entangled states are considered to be a resource to overcome the limitations of a given network structure. In this work, we introduce measures of quantum network-entanglement that are well-defined within the general framework of quantum resource theories, which at the same time have a clear operational interpretation characterizing the extra resources necessary to prepare a targeted quantum state within a given network. In particular, we define the network communication cost and the network round complexity, which turn out to be intimately related to graph-theoretic parameters. We also provide methods to estimate these measures by introducing novel witnesses of network-entanglement.

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Zhen-Peng Xu, Julio I. de Vicente, Liang-Liang Sun, Sixia Yu. 2023-11-23. Quantum network-entanglement measures. https://doi.org/10.22331/q-2025-05-06-1736

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