An international collaboration of researcher from China, Europe, and Australia have demonstrated the precise requirements needed to secure quantum teleportation, a concept that is essential to the future of a quantum internet that lets information to be transmitted securely.
Of course, quantum teleportation doesn’t mean that it’s possible for a person to instantly pop from New York to London, but they can instantly transport information through a bizarre quantum mechanics property called entanglement.
Learn more about the physics behind quantum entanglement in this video from Vertasium.
In the press release, Professor Margaret Reid, from the Swinburne Institute of Technology, explains that the problem with quantum teleportation goes back to how the information is sent along: "Let’s say ‘Alice’ begins the process by performing operations on the quantum state–something that encodes the state of a system–at her station. Based on the outcomes of her operations, she communicates (by telephone or public internet) to ‘Bob’ at a distant location, who is then able to create a replica of the quantum state. The problem is that unless special requirements are satisfied, quantum mechanics demands that the state at Bob’s end will be ‘fuzzed up’.”
However, now, it seems that we have a way to fix this issue.
To avoid the problem, the researchers are employing a very special form of quantum entanglement called ‘Einstein-Podolsky-Rosen steering’. And in the article, which was published in Nature, the team notes the effectiveness of the models: "Our methods establish principles for the development of multiparty quantum communication protocols with asymmetric observers, and can be extended to qubits, whether photonic, atomic, superconducting, or otherwise."
Professor Reid notes that, by using Einstein-Podolsky-Rosen steering’, "Only then can the quality of the transported state be perfect." She adds, "The beauty is that quantum mechanics guarantees that a perfect state can only be transported to one receiver. Any second ‘eavesdropper’ will get a fuzzy version."
In the end, the research provides practical application for quantum steering where a specific measurement is able to have an immediate “steering” effect on a separate and distant state.