A photon’s identity moved without traveling, but what really crossed that distance could redefine how future networks transmit information securely forever.
An international research team including scientists from University of Paderborn has demonstrated quantum teleportation of a photon’s state between two physically separate quantum dots, marking a key step toward scalable quantum communication systems.
The experiment transferred the polarization state of a single photon across a 270 meter free space optical link, without the photon itself physically travelling between the nodes. Instead, the system relied on quantum entanglement between particles, allowing information to be reconstructed at the receiving end. This represents the first successful teleportation between independent quantum emitters rather than a shared source.
The setup combined semiconductor quantum dots, ultra fast single photon detectors, and GPS assisted synchronization to maintain timing precision. Stabilization techniques were used to counter atmospheric disturbances, enabling reliable transmission across open air conditions. The system achieved a teleportation fidelity of up to 82 percent, significantly above classical limits.
Unlike earlier demonstrations that relied on identical photon sources, this work shows that dissimilar quantum dots can be used to transfer quantum information. This is a critical requirement for real world quantum networks, where independent devices must communicate across distributed systems.
The result lays the groundwork for quantum relays and eventually a quantum internet, where information can be transmitted securely using quantum states rather than classical signals. The next step involves entanglement swapping between quantum dots to extend communication distances further.
“Successful quantum teleportation between two independent quantum emitters represents a vital step towards scalable quantum relays and thus the practical implementation of a quantum internet,” says Klaus Jöns, head of the Hybrid Photonics Quantum Devices’ research group and a member of the board of the Institute for Photonic Quantum Systems
