Entanglement of nanophotonic quantum memory nodes in a telecom network. (https://pubmed.ncbi.nlm.nih.gov/38750231/)

These scientists wanted to create a special kind of network that allows information to be sent securely over long distances using quantum mechanics. They used tiny particles called silicon-vacancy (SiV) centers in diamonds to store information. These particles were placed in small cavities that could trap light, and they connected these cavities with fiber optic cables that are used for regular internet connections.

They were able to create a link between two of these tiny particle storage units that were far apart by using light to connect them. They also used the spin of the electrons in these particles and light particles called photons to create a strong connection between the two storage units. They made sure that the connection was very stable by using a special method that involved measuring time.

To make sure that the information stayed secure for a long time, they also used the spin of the nuclei in these particles. They were able to store the connection between the two storage units for a few seconds, which is a long time in the quantum world.

Finally, they were able to send the information between the two storage units over long distances by converting the light particles to a different frequency that can travel through regular fiber optic cables. They tested this by sending information through 40 kilometers of fiber optic cables in Boston.

Overall, these scientists were able to create a network that can send information securely over long distances using tiny particles and light, which is a big step towards creating a larger network that uses quantum mechanics.

Knaut CM., Suleymanzade A., Wei YC., Assumpcao DR., Stas PJ., Huan YQ., Machielse B., Knall EN., Sutula M., Baranes G., Sinclair N., De-Eknamkul C., Levonian DS., Bhaskar MK., Park H., Loncar M., Lukin MD. Entanglement of nanophotonic quantum memory nodes in a telecom network. Nature. 2024 May;629(8012):573-578. doi: 10.1038/s41586-024-07252-z. Epub 2024 May 15.