Quantum key distribution (QKD) is a crucial technology for information security in the future. Developing simple and efficient ways to establish QKD among multiple users are important to extend the applications of QKD in communication networks. This work proposed a scheme of symmetric dispersive optics QKD (DO-QKD) and demonstrated an entanglement-based quantum network based on it. In the experiment, a broadband entangled photon pair source was shared by end users via wavelength and space division multiplexing. The wide spectrum of generated entangled photon pairs was divided into 16 combinations of frequency-conjugate channels. Photon pairs in each channel combination supported a fully-connected subnet with 8 users by a passive beam splitter. Eventually, it showed that an entanglement-based QKD network over 100 users could be supported by one entangled photon pair source in this architecture. It has great potential on applications of local quantum networks with large user number. This paper was accepted at APL Photonics (Volume 5, Issue 7; https://doi.org/10.1063/5.0002595; DOI: 10.1063/5.0002595) and on-line published in July 8th, 2020. The first author and corresponding author of this paper are Ph. D candidate Xu Liu and A/Prof. Wei Zhang, respectively.

Anentanglement-basedquantumnetwork basedonsymmetricdispersiveoptics quantumkeydistribution.pdf