Have you ever been to Ytterby?

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by Sara Marzban

In this post I’m going to briefly describe the solid state system, namely rare-earth crystalline material, that the Tittel lab at Qutech is using to do all sorts of cool quantum communication experiments, including building the hardware required for an elementary link of a quantum repeater.

In this era of online communications, the security of transmitted and received information is extremely important. Quantum communication is an absolutely secure method of communication between points A and B. However, building these secure quantum communication networks has proven to be difficult. In a quantum communication network, fragile quantum states are transmitted between a transmitter (point A) and a receiver (point B). During transmission, decoherence can be introduced into the system, either from losses in the transmission line, absorption in the system or from environmental contamination. Some of the losses occurring over the full length of the transmission line scale exponentially with distance and as a consequence, quantum communication is restricted to a range of about 200 km, beyond which quantum states can no longer be reliably measured [1, 2, 3].
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Diary of an international student at QuTech

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by David Maier


QuTech not only offers a wide range of interesting research, but also a diverse group of employees from numerous countries around the world. As a student from the far away country of Germany I was very curious if I would be able to fit in and overcome the cultural differences. Four months ago I came to Delft for my master’s project. In this little piece I would like to tell you from a humorous perspective about some of the challenges I faced as an international student coming to Delft and how you can overcome them too.

Disclaimer: this text contains irony.
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A quantum network stack?

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by Axel Dahlberg

Summer is approaching fast! The days until vacation are getting fewer and fewer. But before you can relax at a beach with a cold drink you need to send a bunch of emails. However for some reason the software allowing your computer to connect to the Internet has suddenly vanished. What can you do? Well, maybe you can just manually do whatever this software does. It can’t be too hard right? Or can it…?

The network stack, a collection of of software used by computers to connect to each other and run applications over a network, such as e-mail, social media, file sharing, video streaming etc., used by today’s Internet is crucial to its operation. You use it everyday, but do you know what it actually does? When you send an email to your colleague, how is your email actually transmitted across to a different computer?

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