An operating system for executing applications on quantum network nodes

The goal of future quantum networks is to enable new internet applications that are impossible to achieve using only classical communication^1-3. Up to now, demonstrations of quantum network applications^4-6 and functionalities^7-12 on quantum processors have been performed in ad hoc software that was specific to the experimental setup, programmed to perform one single task (the application experiment) directly into low-level control devices using expertise in experimental physics. Here we report on the design and implementation of an architecture capable of executing quantum network applications on quantum processors in platform-independent high-level software. We demonstrate the capability of the architecture to execute applications in high-level software by implementing it as a quantum network operating system-QNodeOS-and executing test programs, including a delegated computation from a client to a server¹³ on two quantum network nodes based on nitrogen-vacancy (NV) centres in diamond^14,15. We show how our architecture allows us to maximize the use of quantum network hardware by multitasking different applications. Our architecture can be used to execute programs on any quantum processor platform corresponding to our system model, which we illustrate by demonstrating an extra driver for QNodeOS for a trapped-ion quantum network node based on a single ⁴⁰Ca⁺ atom¹⁶. Our architecture lays the groundwork for computer science research in quantum network programming and paves the way for the development of software that can bring quantum network technology to society.