“The Coin-toss Check”: Quantum cryptography beyond quantum key distribution

On 16 April 2026, Prof. Dr. Tobias Heindel, newly appointed professor at the Department for Quantum Technology at the University of Münster, gave his inaugural lecture entitled “The Coin-toss Check – How cheating can be avoided in the future quantum internet”. In front of a large audience, he introduced how quantum cryptographic protocols beyond quantum key distribution can contribute to secure communication in future quantum networks. A central focus was a recent publication in Nature Communications, part of the Nature Portfolio, in which quantum strong coin flipping was experimentally implemented using single photons generated by a semiconductor quantum dot. Rather than following a conventional scientific lecture format, Prof. Heindel adopted an accessible approach inspired by “Checker Tobi” with Tobias Krell and KiKA von ARD und ZDF. The lecture combined current research in quantum cryptography with vivid and engaging science communication. A similar format is planned for the Kids Lectures in Münster.

Single-photon advantage in quantum cryptography beyond QKD

Together with researchers from the Technical University of Berlin and the Chinese Academy of Sciences in Beijing, the Photonic Quantum Networks group has demonstrated enhanced security in quantum coin flipping — a fundamental cryptographic building block for scenarios where communicating parties do not trust each other. For the first time, a deterministic single-photon source was used to implement this protocol, achieving a security advantage over both classical methods and previous quantum implementations based on attenuated lasers. The work extends the reach of quantum cryptography beyond quantum key distribution and represents a step towards more complex protocols in a future quantum internet. Read the full interview with Prof. Heindel in the University of Münster news portal.

Original publication: D. A. Vajner, K. Kaymazlar, F. Drauschke, L. Rickert, M. von Helversen, H. Liu, S. Li, H. Ni, Z. Niu, A. Pappa, T. Heindel (2026): Nature Communications 17, 2074; DOI: 10.1038/s41467-026-69995-9

On the way to the quantum internet: Prof. Dr. Tobias Heindel joins the Department for Quantum Technology

We welcome Prof. Dr. Tobias Heindel as a new professor at the Department for Quantum Technology. A profile in wissen|leben presents his research on building blocks for the quantum internet and quantum communication.

Prof. Dr. Tobias Heindel is the new professor of Photonic Quantum Networks at the Department for Quantum Technology and heads the working group of the same name. He conducts research on building blocks for the quantum internet and quantum communication, whose security is based on the laws of quantum physics – including quantum light sources and individual photons (“light particles”).

He is testing these future technologies in laboratory experiments and field trials; his team is currently working on a quantum communication test track between Jena and Erfurt, among other things. For Münster, he is planning a quantum network together with other working groups, which will extend from the Center for Nanotechnology (CeNTech) to the Center for Soft Nanoscience (SoN) and the future IG 1 physics building, in order to test the basic functions of a future quantum internet in a realistic test environment.

With this focus, Tobias Heindel is directly linking up with the orientation of the Department for Quantumtechnology, founded in 2021, whose research, teaching, and transfer activities address topics of quantum information processing, quantum communication, and quantum sensor technology, drawing on modern laboratory infrastructures (including CeNTech and SoN) as well as nanostructuring and characterization capabilities at the Münster Nanofabrication Facility.

Prof. Tobias Heindel erhält den IOP Award „Lise Meitner Medaille und Preis 2025“ für das Wissenschaftskommunikationsprojekt QuanTour

Prof. Tobias Heindel, recently appointed professor at the Department for Quantum Technology at the University of Münster, was awarded the 2025 Institute of Physics Lise Meitner Medal and Prize for the science communication project QuanTour.

According to the jury, the QuanTour project, which Heindel organizes together with his colleague Prof. Dr. Doris Reiter (TU Dortmund), “has made a transformative contribution to the public understanding of quantum science, particularly in the UK and Ireland.”.

In the outreach and OpenScience project QuanTour, a single-photon source travels like an Olympic torch from country to country and is accompanied by new experiments and outreach activities at each site. The journey started in April 2024 and, after its European tour, also made stops in Turkey and Canada. Heindel initiated and organized QuanTour together with his colleague Prof. Dr. Doris Reiter from TU Dortmund with the support of the German Physical Society.

For all those who want to know more: On 15.11.2025, QuanTour and the quantum emitter itself will come to Münster for the first time for the event Quantum100 - the closing event of the quantum year 2025.