Quantum Teleportation Breakthrough Brings the Quantum Internet Closer

Researchers have completed the first demonstration of quantum teleportation between two different quantum dots. The polarization state of a single photon produced by one quantum dot was transferred to another quantum dot at a separate physical location. The experiment used a 270-meter free-space optical link between two buildings at Sapienza University of Rome. The results were published in Nature Communications. An international team carried out the work. It included researchers at Paderborn University, Johannes Kepler University Linz and the University of Würzburg. Scientists at Paderborn spent roughly a decade on optical measurements and data analysis under Professor Klaus Jöns. They collaborated with a group led by Professor Rinaldo Trotta at Sapienza University of Rome. Quantum dots for the experiment were fabricated at Linz. Resonators were produced through nanofabrication at Würzburg. The Rome group ran the teleportation protocol. It used GPS-assisted synchronization along with ultra-fast single-photon detectors and stabilization systems to counter atmospheric turbulence. The process reached a state fidelity as high as 82 plus or minus 1 percent. This value exceeds the classical limit by more than ten standard deviations. Professor Jöns said the experiment shows that quantum light sources based on semiconductor quantum dots could serve as a key technology for future quantum communication networks. He added that successful teleportation between two independent quantum emitters represents a vital step toward scalable quantum relays.