Entanglement distribution quantum networking within deployed telecommunications fibre-optic infrastructure

Abstract

Quantum networks have been shown to connect users with full-mesh topologies without trusted nodes. We present advancements on our scalable polarisation entanglement-based quantum network testbed, which has the ability to perform protocols beyond simple quantum key distribution. Our approach utilises wavelength multiplexing, which is ideal for quantum networks across local metropolitan areas due to the ease of connecting additional users to the network without increasing the resource requirements per user. We show a 10 user fully connected quantum network with metropolitan scale deployed fibre links, demonstrating polarisation stability and the ability to generate secret keys over a period of 10.8 days with a network wide average-effective secret key rate of 3.38 bps.

A study of polarization compensation for quantum networks

“…The results of our measurements based on the sample of 206 compensations on a full-mesh four-user network show that it takes 14 min average per link to achieve average polarization visibility of (98.17 ± 0.04)% after compensation. Our previous research [23] showed polarization stability that corresponds to the average standard deviation of QBER of 0.6% after compensation with manual controllers over a period of 10.8 days. This period includes cooling cycles of superconducting detectors every 24 hours over which the network was not running but it fully recovered its functionality after cycling.…”