Dutch researchers have achieved the first teleportation of quantum information between network nodes that are not directly connected to each other. An essential step in the development of an ultra-secure Internet.
Entanglement is a strange quantum phenomenon involving two distant particles or objects with the same properties, and is the focus of proposals to ensure the privacy of online communications. While one of the main approaches currently being studied relies on a network of connected quantum bits (or qubits) entangled with qubits located elsewhere in the network, this has so far only been demonstrated for neighboring, directly connected nodes.
As part of the work published in the journal Nature, Ronald Hanson and his colleagues from theTechnical University of Delftto Netherlandsconstructed a simple network consisting of three qubit nodes named Alice, bob and charlie. If Alice and charlie were not directly connected (they only shared an indirect link via bob), they were quantum entangled, meaning it was impossible to measure information from one of them without changing the state of the other.
” As Charlie’s quantum state changed, so did Alice’s, and the information somehow teleported through Bob without going through him directly. “, To explain Hanson. ” It’s a kind of teleportation, comparable to those seen in science fiction movies. State or information disappears on one side to reappear on the other, and since it does not physically traverse the gap, no data can be lost either.. »
Although this form of entanglement has been theoretically possible for decades, this is its first real demonstration, relying largely on using specific crystals to store qubits over long periods of time.
Contrary to what one might think, deploying a quantum internet network would not result in an increase in throughput: even if the state of two distant nodes of the network changed instantaneously, users exchanging information/data would devices do this in a conventional, non-quantum-mechanical way.
” There are many potential applications, this would allow for the secure exchange of information, for example by preventing servers from tracing the source of the data they process “, To explain Hanson.
While his team was the first to design and test a quantum network in which non-adjacent nodes are entangled, previous work had investigated other types of quantum communication, particularly involving entangled photons.
” Testing different approaches is essential “, highlighted Karl Adamsof’University of Durhamto United Kingdom. ” We don’t yet know which one will be successful. It can be a hybrid technology. »