Artistic display of quantum teleportation process in network scenarios. Quantum information is passed between non-adjacent nodes of the network. Image courtesy of Scixel for QuTech
The scientists demonstrated the teleportation of quantum information between two non-adjacent nodes in a three-node quantum network. This result is an important step towards a quantum internet. The research was recently published in Nature.
Quantum teleportation can transmit quantum information from one location to another, and has potential application value in secure communication, quantum computing, and next-generation Internet development. Experimental demonstrations of this effect reported so far have been limited to two connected nodes. Teleportation between non-adjacent nodes is critical to the construction of quantum networks, such as the quantum Internet.
The quantum network operated by Sophie Hermans, Ronald Hanson and colleagues at Delft University of Technology in the Netherlands has three nodes connected in a row with fibers — Alice, Bob, and Charlie, with direct connections between Alice and Bob and Bob and Charlie, but not between Alice and Charlie.
The implementation of teleportation first involves neighboring nodes sharing quantum entanglement states, and then quantum exchange is made at the intermediate node Bob, thus forming an entanglement between Alice and Charlie, allowing quantum information to be transmitted directly invisible between them. Completing each step of the process while preserving fragile quantum information requires improvements in the preparation, manipulation, and reading of this quantum state.
Alice, the recipient of teleported quantum information. Inside the black aluminum cylinder, the diamond sample is cooled to -270°C to reduce noise from the environment and achieve quantum control. Image courtesy of Marieke de Lorijn for QuTech
The authors point out that the sharing of information between non-adjacent nodes demonstrated in the study may represent another step towards building a quantum network that can communicate through the teleportation of quantum information.
However, Oliver Slattery of the National Institute of Standards and Technology in Maryland and Yong-Su Kim of the Korea Institute of Science and Technology in the same news opinion article believe that there is still a few steps to go to achieve ubiquitous teleportation technology around quantum networks. The authors conclude that several features of the system need to be improved to support multiple teleportations and build large-scale quantum networks.
One of the diamond samples. The gold structure on the surface of the diamond allows control of the quantum processor. The photo was taken by a light microscope. Image courtesy of Matteo Pompili for QuTech
The researchers are working on a quantum network node where mirrors and filters direct laser beams at the diamond chip. Image courtesy of Marieke de Lorijin for QuTech
“Overall, the author’s results and methods are a major breakthrough that opens up a new dimension in the field.” One reviewer said. Another reviewer also said that highlights of the study include the first realization of a three-node quantum network based on high-order control of 5 qubits, a result that can itself be regarded as a major breakthrough in scalable quantum networks; the first demonstration of unconditional qubit stealth transmission across non-adjacent network nodes, which is a conceptual breakthrough because it simulates the operating state of an actual multi-node quantum network, in which case quantum communication needs to go beyond the simple two-node situation; combined with excellent methodological improvements and innovations. Improvements to the fidelity of local and dual-node quantum states have been mainly drafted. (Source: China Science Daily Jinnan)
Related paper information:https://doi.org/10.1038/s41586-022-04697-y