A team of researchers from QuTech in the Netherlands reports realization of the first multi-node quantum network, connecting three quantum processors. In addition, they achieved a proof-of-principle demonstration of key quantum network protocols. Their findings mark an important milestone towards the future quantum internet and have now been published in Science.

The quantum internet

The power of the Internet is that it allows any two computers on Earth to be connected with each other, enabling applications undreamt of at the time of its creation decades ago. Today, researchers in many labs around the world are working towards first versions of a quantum internet – a network that can connect any two quantum devices, such as quantum computers or sensors, over large distances. Whereas today’s Internet distributes information in bits (that can be either 0 or 1), a future quantum internet will make use of quantum bits that can be 0 and 1 at the same time. ‘A quantum internet will open up a range of novel applications, from unhackable communication and cloud computing with complete user privacy to high-precision time-keeping,’ says Matteo Pompili, PhD student and a member of the research team. ‘And like with the Internet 40 years ago, there are probably many applications we cannot foresee right now.

Co-authors Matteo Pompili (left) and Sophie Hermans (right), both PhD student in the group of Ronald Hanson, at one of the quantum network nodes.

Towards ubiquitous connectivity

The first steps towards a quantum internet were taken in the past decade by linking two quantum devices that shared a direct physical link. However, being able to pass on quantum information through intermediate nodes (analogous to routers in the classical internet) is essential for creating a scalable quantum network. In addition, many promising quantum internet applications rely on entangled quantum bits, to be distributed between multiple nodes. Entanglement is a phenomenon observed at the quantum scale, fundamentally connecting particles at small and even at large distances. It provides quantum computers their enormous computational power and it is the fundamental resource for sharing quantum information over the future quantum internet. By realizing their quantum network in the lab, a team of researchers at QuTech – a collaboration between Delft University of Technology and TNO – is the first to have connected two quantum processors through an intermediate node and to have established shared entanglement between multiple stand-alone quantum processors.

Operating the quantum network

The rudimentary quantum network consists of three quantum nodes, at some distance within the same building. To make these nodes operate as a true network, the researchers had to invent a novel architecture that enables scaling beyond a single link. The middle node (called Bob) has a physical connection to both outer nodes (called Alice and Charlie), allowing entanglement links with each of these nodes to be established. Bob is equipped with an additional quantum bit that can be used as memory, allowing a previously generated quantum link to be stored while a new link is being established. After establishing the quantum links Alice–Bob and Bob–Charlie, a set of quantum operations at Bob converts these links into a quantum link Alice-Charlie. Alternatively, by performing a different set of quantum operations at Bob, entanglement between all three nodes is established.

Researchers work on one of the quantum network nodes, where mirrors and filters guide the laser beams to the diamond chip.

Ready for subsequent use

An important feature of the network is that it announces the successful completion of these (intrinsically probabilistic) protocols with a “flag” signal. Such heralding is crucial for scalability, as in a future quantum internet many of such protocols will need to be concatenated. ‘Once established, we were able to preserve the resulting entangled states, protecting them from noise,’ says Sophie Hermans, another member of the team. ‘It means that, in principle, we can use these states for quantum key distribution, a quantum computation or any other subsequent quantum protocol.’

Quantum Internet Demonstrator

This first entanglement-based quantum network provides the researchers with a unique testbed for developing and testing quantum internet hardware, software and protocols. ‘The future quantum internet will consist of countless quantum devices and intermediate nodes,’ says Ronald Hanson, who led the research team. ‘Colleagues at QuTech are already looking into future compatibility with existing data infrastructures.’ In due time, the current proof-of-principle approach will be tested outside the lab on existing telecom fibre – on QuTech’s Quantum Internet Demonstrator, of which the first metropolitan link is scheduled to be completed in 2022.

Higher-level layers

In the lab, the researchers will focus on adding more quantum bits to their three-node network and on adding higher level software and hardware layers. Pompili: ‘Once all the high-level control and interface layers for running the network have been developed, anybody will be able to write and run a network application without needing to understand how lasers and cryostats work. That is the end goal.’

Source: QuTech news item

QuiX, located at Kennispark Twente and cooperation partner of the ANP cluster for Applied Nanotechnology at the University of Twente, confirms with this sale that it is a leader in the world of light technology. With this photonics technology, they are making an important contribution to the development of the first quantum computers. These do not yet exist, but their introduction is coming ever closer. These computers are going to change the world radically, is the prediction. Just think of personalised medication. With quantum computing, it is possible to calculate exactly what the composition and quantity of a medicine should be for an individual. However, the fields of application are much broader. The technology can be used in sectors such as MedTech, the chip industry and agriculture. What is the best time to sow (precision agriculture), can you ‘smell’ cancer through your breath and therefore detect it earlier, and when does an aircraft need specific maintenance? The trick is to calculate exactly what the right moment is, with the help of a computer that can make unprecedented calculations.

Photonic processors from QuiX

QuiX develops quantum photonic processors for quantum information processing and simulation. Using the proprietary TriPleX platform, QuiX provides unique quantum photonic processors that are not only large-scale and fully reconfigurable but also low loss and widely transparent to all suitable quantum light sources. QuiX demonstrated the world’s largest quantum photonic processor in a product launch last December, which can be found here:

QONTROL as first consumer

Qontrol, based in Bristol (UK), makes control electronics and supporting infrastructure for complex, massively multi-channel photonic integrated circuits (PICs). These PICs are now finding uses from telecommunications to fundamental science, and Qontrol’s products can be found powering them, in research labs worldwide.

Jelmer Renema, CTO of QuiX: “This is great news for QuiX. Qontrol is one of the leading quantum photonics technologies companies in Europe. This shows how QuiX can meet the most stringent technological requirements for quantum photonics.”

“We are thrilled and honoured to be the first to be able to kick the tires on QuiX’s awesome new line of photonic processors,” said Dr Josh Silverstone, Qontrol’s CTO. “With this device in our Bristol labs, we will be able to better understand and serve our customer’s needs, and particularly those customers wanting to put QuiX’s technology to use. It will be a fantastic tool for us to demonstrate what our own products can do, too, with the device’s visible-light capability promising to make for fabulous live demos.”

Dankzij het kweken van orgaanweefsel op een geavanceerde chip zou in de toekomst elke patiënt het perfecte medicijn kunnen krijgen. Nederlandse start-ups met deze technologie trekken wereldwijd de aandacht.

Lees meer 

Op een dag zal een dokter, als je bij hem komt met hartproblemen, een stukje huid van je nemen, een klein hart op een chip kweken met jouw genetische achtergrond, en daarop medicijnen uitproberen”, voorspelt Nikolas Gaio van de start-up BI/OND uit Delft. Deze spinoff van de Technische Universiteit Delft, opgericht door drie van oorsprong Italiaanse en Costa Ricaanse aio’s (assistenten in opleiding, red.) van de TU, heeft een plekje weten te bemachtigen op de prestigieuze Start-up Grind Conference in Silicone Valley die komende week plaatsvindt.

Het bedrijf ontwikkelt de hardware die biomedische wetenschappers kunnen gebruiken om met levende cellen organen na te bootsen. De techniek in de chip kan de hartcellen als het ware laten kloppen en bootst een stroming van het bloed na, die de hartcellen van voedingsstoffen voorziet. “Je kunt chips laten kloppen als een hart, laten ademen als een long, of laten stromen als bloed, maar dan allemaal op piepkleine schaal”, zegt Gaio over deze organ-on-chip-techniek.

Doel van BI/OND, is om gepersonaliseerde chips van verschillende organen van een patiënt te maken, die gebruikt kunnen worden om medicijnen te testen voordat ze toegediend worden.”

De behoefte om tot deze zogenoemde personalised medicine te komen heeft onder meer te maken met de beperkte genetische basis waarop medicijnen vaak zijn gebaseerd. Lees verder Bron: Trouw

Beeld BI/OND
De chip zo groot als een vingernagel en biedt plaats voor de kweek van ­lichaamscellen van de patiënt.