Experimental demonstration of an active quantum key distribution network with over gbps clock synchronization

We demonstrate a three-node QKD network that allows multiple users to share secure keys. This QKD network operates on the 850 nm and 1550 nm wavelengths at 1.25 Gbps clock rate. The communication route is controlled by MEMS optical switches. In this paper, we report the network structure and experimental results including the performance of the optical switch, polarization recovery, and timing alignment technology during switching. This demonstration experimentally shows that QKD can be extended to active multi-node networks.