Quantum network facilitates the secure transmission of information between different users. Establishing communication links among multiple users in a scalable and efficient way is important for realizing a large-scale quantum network. Here we develop an energy-time entanglement-based dense wavelength division multiplexed network based on an integrated silicon nitride micro-ring resonator, which offers a wide frequency span (covering at least the entire C-band) and narrow bandwidth modes (~ 650MHz). Six pairs of photons are selected to form a fully and simultaneously connected four-user quantum network. The observed quantum interference visibilities are well above the classical limits among all users. Each pair of users perform the BBM92 protocol for quantum key distribution. Our results pave the way for realizing large-scale quantum networks with integrated photonic architecture.
@article{arxiv.2206.09785,
title = {Realizing an entanglement-based multi-user quantum network with integrated photonics},
author = {Wenjun Wen and Zhiyu Chen and Liangliang Lu and Wenhan Yan and Wenyi Xue and Peiyu Zhang and Yanqing Lu and Shining Zhu and Xiao-song Ma},
journal= {arXiv preprint arXiv:2206.09785},
year = {2022}
}