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arXiv · 1907.08229

A trusted-node-free eight-user metropolitan quantum communication network

Siddarth Koduru Joshi·Djeylan Aktas·Sören Wengerowsky·Martin Lončarić·Sebastian Philipp Neumann·Bo Liu·Thomas Scheidl·Guillermo Currás-Lorenzo·Željko Samec·Laurent Kling·Alex Qiu·Mohsen Razavi·Mario Stipčević·John G. Rarity·Rupert Ursin
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Abstract

Quantum communication is rapidly gaining popularity due to its high security and technological maturity. However, most implementations are limited to just two communicating parties (users). Quantum communication networks aim to connect a multitude of users. Here we present a fully connected quantum communication network on a city wide scale without active switching or trusted nodes. We demonstrate simultaneous and secure connections between all 28 pairings of 8 users. Our novel network topology is easily scalable to many users, allows traffic management features and minimises the infrastructure as well as the user hardware needed.

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Siddarth Koduru Joshi, Djeylan Aktas, Sören Wengerowsky, Martin Lončarić, Sebastian Philipp Neumann, Bo Liu, Thomas Scheidl, Guillermo Currás-Lorenzo, Željko Samec, Laurent Kling, Alex Qiu, Mohsen Razavi, Mario Stipčević, John G. Rarity, Rupert Ursin. 2019-07-18. A trusted-node-free eight-user metropolitan quantum communication network. https://doi.org/10.1126/sciadv.aba0959

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