At Sapienza University of Rome, two physics buildings named after famous scientists face each other across an open space. Last year, researchers achieved something remarkable between these buildings: they teleported a particle of light.
Quantum teleportation does not move the light itself. Instead, it transfers the quantum state of a photon from one location to another using special technology. The photon's information vanished in one building and reappeared in the other, 270 metres away.
An international team from Paderborn University in Germany and Sapienza University successfully teleported light between two different semiconductor quantum dots for the first time. The light arrived with 82 percent accuracy, which proved the process was genuinely quantum and not a trick.
The challenge was that the two quantum dots were not identical. Researchers had to make them match by using magnetic fields and carefully controlled pressure. They also had to keep the 270-metre air link stable against wind and temperature changes, using special detectors to catch the arriving photons.
Prof. Klaus Jöns from Paderborn University explained that semiconductor quantum dots could become important technology for future quantum communication networks. Prof. Rinaldo Trotta from Sapienza led the Italian part of the research.
This experiment is a key step toward building a real quantum internet. It shows that different solid-state light sources can work together for quantum communication.