The University of Stuttgart team has, for the first time, teleported a quantum state between photons emitted by two separate quantum dots, demonstrating a pathway for transmitting quantum information across networks. The experiment used roughly 10 meters (about 33 feet) of standard optical fiber and achieved a success rate slightly above 70%. This work shows quantum-dot emitters can produce indistinguishable photons from different sources — an important step toward a practical quantum internet.
World First: Quantum State Teleported Between Photons from Separate Sources
The University of Stuttgart team has, for the first time, teleported a quantum state between photons emitted by two separate quantum dots, demonstrating a pathway for transmitting quantum information across networks. The experiment used roughly 10 meters (about 33 feet) of standard optical fiber and achieved a success rate slightly above 70%. This work shows quantum-dot emitters can produce indistinguishable photons from different sources — an important step toward a practical quantum internet.
02:38 PM, 11/21/2025Technology
A research team led by the University of Stuttgart has achieved a milestone for quantum communications by teleporting a quantum state between photons emitted by two independent light sources for the first time. The result brings a practical quantum internet one step closer by demonstrating a method to relay quantum information across separate emitters without loss or corruption.
Conventional optical networks amplify light signals as they travel, but quantum information cannot be copied or amplified in the same way. Preserving quantum data requires sources that produce essentially identical photons. Semiconductor devices called quantum dots can emit photons with tightly controlled frequencies and properties, making photons from different dots effectively indistinguishable — a key requirement for teleportation of quantum states.
How the experiment worked
The team used two independent quantum-dot sources and successfully transferred the quantum state from a photon produced by one dot to a photon from the other. The experiment was conducted over standard optical fiber of about 10 meters (nearly 33 feet), demonstrating compatibility with existing network cabling. The reported teleportation success rate in this setup was just above 70%.
"For the first time worldwide, we have succeeded in transferring quantum information among photons originating from two different quantum dots," said physicist Peter Michler of the University of Stuttgart.
Although popularly called "teleportation," the process transfers the quantum state of a photon rather than the photon itself. For the transfer to work, the participating photons must be in a coherent quantum condition and be indistinguishable in their other properties. Quantum dots restrict variations between photons from separate emitters, enabling state transfer across independent sources.
The use of a standard optical fiber in the demonstration suggests that early quantum links could be built on existing infrastructure. Nonetheless, researchers note several challenges remain: increasing the distance over which such teleportation is reliable, improving the success probability, and integrating these components into larger networks with repeaters and error correction.
"These results demonstrate the maturity of quantum dot–based technology and provide an important building block for future quantum communication networks," the team concluded. The study appears in Nature Communications.