Breakthrough Experiment Paves the Way for Quantum Internet
A recent experiment conducted by a team at the University of Stuttgart in Germany has brought us one step closer to a quantum internet. Physicists have successfully teleported a quantum state between photons produced by separate light sources for the first time, marking a significant milestone in quantum communication.
This breakthrough achievement enables engineers to transmit quantum information through repeating stations made up of ‘quantum dots’ over long distances without any loss or disruption. Unlike traditional internet cables that use amplifiers to boost data-carrying light signals, quantum information requires sources of light that can generate nearly identical photons.
Quantum dots, special semiconductors capable of emitting photons with precise frequencies, play a crucial role in this experiment. These quantum dots emit light waves at incredibly accurate frequencies, making it impossible to distinguish photons from different dots.
Researchers have successfully teleported quantum information between photons originating from two separate quantum dots, demonstrating the feasibility of safeguarding quantum data across networks. Physicist Peter Michler from the University of Stuttgart describes this achievement as a significant milestone in the development of the quantum internet.

While the term “teleportation” is commonly used in quantum physics experiments, what actually occurs is the transfer of a quantum state between photons. The photons do not disappear from one location and appear in another; instead, they maintain a fuzzy quantum form and must be indistinguishable from each other for the transfer to be successful.
Using quantum dots to restrict photon characteristics allows teleportation to occur between separate locations with different sources. The researchers utilized a standard optical fiber cable, similar to those used in current online networks, emphasizing the importance of leveraging existing infrastructure for the quantum internet.
Michler highlights that transferring quantum information between photons from different quantum dots is a crucial step towards achieving longer distances in quantum communication. The researchers aim to enhance the teleportation success rate, which currently stands at over 70 percent, and extend the distance over which quantum information can be transmitted.
Published in Nature Communications, this research underscores the potential of quantum dot-based technology as a foundational element for future quantum communication networks.
Source: Nature Communications

