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.
@article{arxiv.1907.08229,
title = {A trusted-node-free eight-user metropolitan quantum communication network},
author = {Siddarth Koduru Joshi and Djeylan Aktas and Sören Wengerowsky and Martin Lončarić and Sebastian Philipp Neumann and Bo Liu and Thomas Scheidl and Guillermo Currás-Lorenzo and Željko Samec and Laurent Kling and Alex Qiu and Mohsen Razavi and Mario Stipčević and John G. Rarity and Rupert Ursin},
journal= {arXiv preprint arXiv:1907.08229},
year = {2022}
}