The first operating system for quantum networks has been built

Linking quantum computers to each other just became easier, as researchers have created the first operating system for quantum networks.

“You don’t make a quantum network useful by only building hardware,” says Stephanie Wehner at the Delft University of Technology in the Netherlands. She has long worked on connecting quantum computers into networks that would allow them to exchange information extremely securely and run calculations in new ways, but this requires understanding the technical nitty-gritty of each device involved. Together with her colleagues, Wehner has now developed a way to operate quantum networks more universally.

The operating system the team built is software that can to control the devices within a quantum network regardless of the type of qubits, or quantum bits, that make them up. Controlling devices like this is made more difficult by the fact that networked quantum computers receive both quantum information from other quantum computers as well as traditional signals from classical computers that help interface with them.

To show that their operating system, called QNodeOS, can handle both, the researchers tested it with two different kinds of quantum computers, and several different tasks. They used two quantum computers made from specially processed diamonds, and another made from electrically charged atoms. With these two types of quantum hardware, the researchers ran a test program for delegated quantum computing – similar to using your laptop to perform a calculation in the cloud. They also tested the ability of QNodeOS to handle multitasking by running two programs at once.

Joe Fitzsimons at the quantum computing start-up Horizon Quantum, based in Singapore and Ireland, says this is a significant advance in laying down the foundations for a quantum internet. He says that “once you start taking the idea of building general-purpose quantum networks seriously, there ends up being a lot of work to do”, and this new operating system leads to a long list of things to develop next, such as routing protocols.

Wehner says developing QNodeOS has been like drawing up a colouring page – they have outlined all the shapes and will now be hard at work colouring them all in. For instance, the work raised the question of how to write scheduling programs for a quantum network. “This wasn’t even on my radar before, but now I am so excited about it,” she says.