We pursue different milestones in the Quantum Internet Division.

As a first step towards the World’s first entanglement based quantum internet, we aim to connect two quantum nodes located in Delft and The Hague. This initial quantum link will be extended with other quantum nodes connecting multiple locations and increasing the functionality of the quantum network. Important milestones that we already passed on the road to a quantum internet are the first ‘loophole-free Bell test’, in which entanglement was achieved between two quantum nodes connected by fibre-optic cables of 1.3 km and the first on–demand quantum entanglement generation in 2018. Also, in 2021, we report realization of the first multi-node quantum network, connecting three quantum processors.

As well as hardware components, a quantum internet will require specialist software to control the hardware and internet traffic. A QuTech team has written an IETF draft of the world’s first link layer protocol, the adoption of which will make the realization of entanglement in a fundamental physics experiment a clearly defined network service. Other significant topics include development of a comprehensive quantum internet stack design featuring both hardware and software, and ensuring interoperability between network layers.

We’re exploring techniques such as quantum memories and quantum repeaters, which are basic components needed for extending quantum networks over even longer distances, and increasing its functionality. By connecting two quantum nodes more than 1 km apart via several rounds of entanglement generation and purification, we want to demonstrate the quantum repeater principle.

Working towards a networked quantum computer, we aim to demonstrate the use of a networked quantum computer to execute a small-scale distributed quantum algorithm. Quantum Error Correction is essential in this process such that quantum systems become more stable with increasing size.