A Single-Atom Light Switch

With just a single atom, light can be switched between two fibre optic cables at the Vienna University of Technology. Such a switch enables quantum phenomena to be used for information and communication technology. Fibre optic cables are turned in to a quantum lab: scientists are trying to build optical switches at the smallest possible scale in order to manipulate light. At the Vienna University of Technology, this can now be done using a single atom. Conventional glass fibre cables, which are used for internet data transfer, can be interconnected by tiny quantum systems. Light in a Bottle - Professor Arno Rauschenbeutel and his team at the Vienna University of Technology capture light in so-called "bottle resonators". At the surface of these bulgy glass objects, light runs in circles.