Chinese Physicists’ Experiment with Sunlight Could Help Enable Teleportation, Cryptography

(PhysicsWorld) The first unambiguous proof that light from a thermal source behaves quantum mechanically has been claimed by Chao-Yang Lu, Jian-Wei Pan and colleagues at the University of Science and Technology of China in Shanghai. Their demonstration involved interfering single photons from one distant thermal source – the Sun – with photons from a semiconductor quantum dot here on Earth. They say that their work could help enable teleportation, cryptography and other quantum technologies, as well as provide new insights into stellar astrophysics.
According to Lu, the team’s work could contribute to building large-scale hybrid quantum information networks by allowing independent photon sources to interact with one another. One such application that might benefit, he says, is quantum teleportation. That involves transferring quantum states over long distances without the movement of physical particles. Teleportation requires that the sender interfere one half of an entangled group of photons with another group – those bearing the states to be transmitted.