Junpeng Zhang

Quantum networks revolutionize the way of information transmission and are an essential step in building a quantum internet. Generally, the information capacity per user-channel in a quantum network drastically decreases with the increase of network capacity, making it difficultly scale to large-user scenarios. To break this limit, we propose a network capacity-independent quantum network (NCI-QN) that maintains constant information capacity per user-channel regardless of network scale, overcoming the scalability bottleneck in conventional quantum networks. The architecture employs a multi-mode time-frequency framework, with theoretical analysis extending PLOB and Holevo bounds to network scenarios to establish capacity independence. Experimentally, we demonstrate a 19-user NCI-QN using optical frequency combs in quantum key distribution, achieving a record 8.75 Gbps composable finite-size secure key rate.