Stitching Qubits

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How to add qubits to an array one by one.

by Anne-Marije Zwerver

So it is winter and it is cold. Cold? It is freezing! But the air is nice and dry outside, so you decide to take a wintery walk in the forest. If you’re in a part of the world where you can currently fry an egg on the street, just wander along in your head – this is a small gedanken experiment. The walk is nice, yet cold and by the time you arrive home, the only thing you want, is to take a nice and warm shower. You turn on the tap and you feel the water running, splashing on your arms and shoulders, slowly defrosting your fingers. But then, for goodness sake, your roommate turns on her (cold) tap and your water temperature rises instantly. In a reflex, you jump out of the water jet, your skin already showing red stains. Luckily it was just an instant and soon you can go back into the shower. But then, of course, your other roommate needs some hot water and with a scream you, again, jump out of the now ice-cold shower. Time for a cup of tea…

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How can we speed up the quantum internet?

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by Suzanne van Dam

What if we could make an internet, but quantum? This would allow us to connect distant nodes (e.g. computers) not with classical information, but with quantum information. We can already imagine cool applications, such as secure communication
guaranteed by the laws of quantum physics. But many of the applications may not even have been dreamed up yet,
as happened before with new technology.
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A Quantum Internet made of Diamonds

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How cool is that? A Quantum Internet. Made of Diamonds.

by Matteo Pompili

We are constantly connected to Internet. With our computers, our smartphones, our cars, our fridges (mine is not, yet, but you get the idea). In its very first days, the Internet was a very rudimentary, yet revolutionary, connection between computers [1]. It enabled one computer on the network to send messages to any other computer on the network, whether it was directly connected to it (that is, with a cable) or not. Some of the computers on the network acted as routing nodes for the information, so that it could get directed toward the destination. In 1969 there were four nodes on the then-called ARPANET. By 1973 there were ten times as many. In 1981 the number of connected computers was more than 200. Last year the number of devices capable of connecting to Internet was 8.4 billion (with a b!) [2].
Computers on their own are already great, but there is a whole range of applications that, without a network infrastructure, would be inaccessible. Do you see where I am going?
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Looking back at the DiVincenzo criteria

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by David DiVincenzo

The first time that I heard that there were “DiVincenzo criteria” was when Richard Hughes of Los Alamos contacted me in the fall of 2001, telling me that ARDA (predecessor of IARPA – a funding agency of the US intelligence services) had commissioned him to form a roadmap committee to forecast the future of quantum information technology [1]. Before that, I just thought of them as a list that I showed in various talks and wrote down in a few essays. So the fact that they have become a “thing” is basically because some government bureaucrats found them a handy way to draw up metrics for the progress of their quantum computing programs.

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