Innsbruck begins building a quantum internet prototype linking cities hundreds of kilometres apart

[veritas.io]

The University of Innsbruck has started work on a prototype quantum internet as part of the European Quantum Internet Alliance. The aim is to connect trapped ion quantum computers across hundreds of kilometres using existing optical fibre. The European Commission has allocated 47.5 million euros to the alliance, with 5.4 million going to the Innsbruck teams. The wider project involves over 50 institutions in 12 EU countries and is led by TU Delft

The effort in Innsbruck is led by Tracy Northup and Ben Lanyon from the Department of Experimental Physics, working with local quantum company AQT. The prototype will have three trapped ion quantum computers organised into two metropolitan scale networks. Quantum repeaters, supplied by collaborators in Barcelona, will carry the connection over the long fibre link between the two networks. Northup said the goal is to link together two metropolitan scale networks of ion trap quantum computers over hundreds of kilometres

Quantum repeaters are the key piece. Photons get lost in fibre over long distances, and unlike normal internet signals you cannot simply copy and amplify a quantum state. Repeaters get around that by using entanglement swapping to extend the connection in stages. Showing that they work between real networks would be a major milestone. Getting the timing and memory right at each repeater is extremely hard

The team has three and a half years to bring the hardware, software and network components together into a fully programmable prototype. QIA director Stephanie Wehner said it may become the first of its kind in the world. Europe has invested heavily in quantum networking, and this is a chance to show results

Innsbruck has a long history in trapped ion physics, so it is a natural place for this. What would you use a quantum internet for? Secure communication is the obvious answer, but linking quantum computers together could matter even more. Europe's other big quantum bets are mostly on computing hardware, so networking is a nice counterweight

Quantum internet prototype takes shape in Innsbruckwww.uibk.ac.at

[Freddie51]

AQT being local helps a lot. Having a company next door that builds trapped ion systems makes the collaboration much easier. It is a nice example of a university spinout feeding back into research. Spinouts staying near their university is good for everyone

[Owen84]

First of its kind is a bold claim. China has done a lot of quantum networking work too. It will be interesting to see how they compare. Their satellite work in particular was years ahead

Europe has some catching up to do. A bit of competition will push both forward

[NatureBoyRyan65]

Linking quantum computers is the more exciting part for me. If you can connect several smaller machines, you get around some of the scaling problems

It is the same idea as networking ordinary computers. Distributed quantum computing could be the way round the size limits of a single trap. Each node stays manageable

[Firewall Rosie]

Secure communication is still the main selling point for governments. Quantum keys that reveal any eavesdropping are attractive for banks and the military. That is where the early money will come from. Money follows security

[InferenceLoop65]

Forty seven and a half million euros sounds like a lot, but split across 50 institutions it is modest. Europe tends to spread funding thinly. The US and China put much bigger sums into fewer places

[Andy99]

Three and a half years is a reasonable timescale for something this ambitious. Plenty could go wrong along the way. But Innsbruck and Delft are two of the strongest groups in the world for this