The rules of quantum mechanics enable fundamentally new applications that would be impossible in a world governed by classical physics: quantum computers hold the promise to solve classically intractable problems, quantum communication can achieve unconditionally secure communication, and quantum metrology enables measurements beyond the limits of classical laws. A long-sought goal for extending the reach of quantum technologies across the globe is to realize a quantum network for the distribution of entanglement between multiple distant parties. Groundbreaking demonstrations have been possible thanks to optically active solid-state spin systems, providing the possibility to interconnect long-lived quantum memories, in the form of electron and nuclear spins, via traveling single photons, which are ideal long-distance information carriers. The big challenge today concerns the scaling of proof-of-concept demonstrations into practical applications.
With the project “Integrated multi-qubit devices for scalable quantum networks” we aim at investigating the optical and spin properties of novel color centers in diamond, which could provide performances beyond what offered by established qubit systems, such as higher operating temperatures and faster optical communication rates. Furthermore, we will investigate the use of diamond photonic nanostructures and photonic integrated circuits. By taking advantage of the scalability of modern nanofabrication processes, it will be possible to integrate on a single device a large number of quantum memories, where they can be individually and precisely manipulated by integrated electronics and photonics circuits. The capabilities of these devices will then be tested by implementing quantum networking protocols. A successful project will make diamond-based quantum communication devices compatible with existing information and communication technologies, opening the way for their deployment in real-world applications.
