Networking goes quantum

A scientist involved in expanding quantum communication to a network of users, is continuing his work at the University of Bristol. The enhanced cyber security offered by quantum communication has been historically limited to two partner exchanges, now for the first-time scientists have connected multiple users simultaneously on a quantum encrypted network without using trusted nodes. Researchers from the Institute of Quantum Optics and Quantum Information (IQOQI) of the Austrian Academy of Sciences, together with a collaborator from the Austrian Institute of Technology (AIT), report on the simple, seamless, cheap and secure network in the latest issue of the journal Nature , published today. Co-author of the paper Dr Siddarth Joshi who recently moved to the University of Bristol and is continuing to develop quantum networks in the Quantum Engineering Technology Labs , said: "We created a very versatile quantum communication network where every user can talk to every other user simultaneously. "We plan to build even bigger networks with many more users, with the goal to create a versatile foundation for building a quantum internet." The Viennese team achieved the long-awaited quantum network using a novel architecture based on a new method of distributing a basic resource of quantum communication -entanglement. An entangled system is one which is interconnected to such a degree that the individual parts can't be fully described in isolation. Entangled light particles, photons, are the fundamental resource used in quantum communication to distribute a secure encryption key.