The first version of a quantum internet in the making

Delft researchers at QuTech generated quantum entanglement between two quantum chips faster than the entanglement was lost. This means that a major hurdle in developing a useful quantum network has been cleared.

Entanglement – once referred to by Einstein as “spooky action” – forms the link that will provide a future quantum internet with its power and fundamental security. By exploiting the power of quantum entanglement, it is theoretically possible to build a quantum internet that cannot be eavesdropped on.

However, in order to realize this, you have to be able to create entanglement reliably, ‘on demand’, and maintain it long enough to pass the entangled information to the next node. So far, this has been beyond the capabilities of quantum experiments.

But now, scientists at QuTech in Delft, from the group of Ronald Hanson, have been able to generate entanglement experimentally over a distance of 2 m in a fraction of a second, ‘on demand’, and subsequently maintain this entanglement long enough to enable further entanglement – in theory – to a third node.

“These results demonstrate a key building block for extended quantum networks and open the door to entanglement distribution across multiple remote nodes,” the researchers wrote in their article published in Nature on June 14. “The challenge is now to be the first to create a network of multiple entangled nodes: the first version of a quantum internet,” Hanson adds. “We still have to develop a network with three nodes. Our experiments (published in Nature) have demonstrated that this is achievable.”