Measurement-device-independent quantum key distribution for metropolitan network

Abstract

Since its initial proposal in 2012, measurement-device-independent quantum key distribution (MDIQKD) has inspired rapid experimental progress as it is invulnerable to all detector side-channel attacks and ideally suitable for quantum key distribution (QKD) networks with star-topology, such as metropolitan networks. The main goal of this thesis is to develop MDIQKD systems for building a cost-effective metropolitan quantum network. Towards this end, we experimentally demonstrate the coexistence of MDIQKD with classical communication on the same fibre. This eliminates the use of dark fibre for quantum communication and minimises implementation costs by utilising the existing fibre infrastructure. Additionally, we move the quantum channel from the third telecommunication window (1530-1565 nm) to second (1260-1360 nm) to ensure MDIQKD can co-exist with classical communication rates of over 10-terabits per second. Furthermore, we enhance the performance of the MDIQKD systems by increasing the repetition rate from 20MHz to 200MHz and improve flexibility and reliability to facilitate the deployment of a metropolitan quantum network.