The project was published in Physical Review Letters and funded by the Engineering and Physical Sciences Research Council. The University of Oxford and the University of Edinburgh also took part in the study.
The scientists created a new approach that “bridges the gap between the theoretical promise of perfect security guaranteed by the laws of quantum physics and the practical implementation of such security in large networks”.
Lead author Dr Ciarán Lee, who specialises in physics and astronomy at UCL, said: “We’re in a technology arms race of sorts. When quantum computers are fully developed, they will break much of today’s encryption whose security is only based on mathematical assumptions.
“Our approach works for a general network where you don’t need to trust the manufacturer of the device or network for secrecy to be guaranteed. Our method works by using the network’s structure to limit what an eavesdropper can learn,” said Dr Matty Hoban, from the University of Oxford.
Up until now, there’s been little research exploring communication over quantum networks. And previous findings have focused on what’s possible between two devices.
“In future work, we’d like to work with partners in the UK national quantum technologies programme to develop this further. We hope to trial our quantum network approach over the next few years.”
Dr Lee added: “Our work can be thought of as creating the software that will run on hardware currently being built to realise the potential of quantum communications.