Physik in unserer Zeit reports on Quantum Teleportation using Semiconductor Quantum Dots –
Quantum Networks have gained increasing importance in research in recent years. They are considered a foundation for future secure communication systems and could, in the long term, also enable the networking of Quantum Computers or a Quantum Internet. A central role in this context is played by Quantum Teleportation as a fundamental principle of Quantum Communication. It enables the transfer of the Quantum State of a photon to another photon without directly measuring the underlying information. In this way, long distances can be bridged and losses during transmission can be avoided. Against this background, researchers from the QR.N consortium at the sites Stuttgart, Saarbrücken, and Dresden have achieved an important advance in semiconductor-based Quantum Light Sources, which was published last year in Nature Communications. These results are now also featured in a report published in the current issue (May 2026) of the journal Physik in unserer Zeit.
In the experiment, the researchers succeeded for the first time in teleporting Quantum States of photons from different semiconductor light sources – an important step towards future Quantum Repeaters. These are based, among other things, on the transfer of photonic Quantum States. Epitaxially grown semiconductor Quantum Dots were used as Quantum Emitters. These nanoscale structures have been studied for many years and are capable of generating single photons as well as entangled photon pairs, thereby forming a key foundation for experiments in Quantum Teleportation.
For the experiment, the research group of Dr. Caspar Hopfmann at the Leibniz-Institut für Festkörper- und Werkstoffforschung (IFW) Dresden fabricated specific semiconductor structures. Two separate Quantum Dots on different samples were selected to generate the required photons. A central challenge was to precisely match the properties of the photons. For this purpose, Quantum Frequency Converters were used, developed at Universität des Saarlandes (UdS) in the research group of Prof. Dr. Christoph Becher. They make it possible to compensate for even the smallest differences in photon wavelength and to adapt them precisely to existing optical fiber standards. This makes the experiment compatible with existing fiber-optic infrastructure.
The result of the experiment represents an important milestone for the transfer of Quantum States and the development of future Quantum Repeaters. While Quantum Teleportation has already been demonstrated with other systems, the Quantum Dot Platform offers the advantage of seamless integration into existing semiconductor technologies. As a reliable single-photon source, it also opens up additional prospects for secure Quantum Communication.
Source reference: https://onlinelibrary.wiley.com/doi/10.1002/piuz.70067
