“We believe we are at a vey special point in time, analogue to the start of the Internet today,” said David Elkouss, a researcher in the Quantum Internet and Networked Computing (QINC) group at the Technical University of Delft speaking at the BQIT quantum conference in Bristol this week.
Rather than sending quantum keys over point-to-point optical fibres, the quantum network will have links between Delft, Amsterdam, Leiden and The Hague carrying quantum bits and is planned for next year. This would allow each bit to be intrinsically secure as each photon is paired, or entangled, with another. Interference with one photon destroys the other, creating a highly secure network.
“The grand challenge is for long distance communications and there has been recent very exciting developments with the functional repeater experiments with ultra low loss fibre to 500km,” he said. “But we want to go beyond this point to point network and demonstrate a platform independent network in 2020 between Amsterdam, Leiden, The Hague and Delft.” This will carry quantum keys but also be able to store and manipulate qubits at each node.
“In stage three [of the network] we introduce memory, storing qubits. A new set of protocols become possible for teleportation, cryptography and blind quantum computing using remote quantum servers. This we believe will be possible in the near future, the 2020 network should be a quantum memory network,” he said.
The team at QINC are simulating networks with 9 nodes using a tool called NetSquid. “We are on version 0.5 which means there are still some rough edges but we expect to release v1.0 by the end of the year,” he said. The next stage is to simulate a network with 1000 nodes.
“We are using NetSquid to model large quantum networks, developing the hardware models and in Q1 2021 we will have a hybrid large quantum network simulation, working with the supercomputer at Leiden University.”