Physicists at MPQ control the optical properties of a single atom!
Due to the continued miniaturization of computer chip components, we are about to cross a fundamental boundary where technology can no longer rely on the laws of the macroscopic world. With this in mind, scientists all over the world are researching technologies based on quantum effects that can be used to communicate and process information. One of the most promising developments in this direction are quantum networks in which single photons communicate the information between different nodes, e.g. single atoms. There the information can be stored and processed. A key element in these systems is Electromagnetically Induced Transparency (EIT), an effect that allows to radically change the optical properties of an atomic medium by means of light. Previously, scientists have studied this effect and its amazing properties, using atomic ensembles with hundreds of thousands of atoms. Now, scientists in the group of Prof. Gerhard Rempe, Director at the Max Planck Institute of Quantum Optics (MPQ) in Garching and Head of the Quantum Dynamics Division, have managed to control the optical response of a single atom using laser light (Nature, Advanced Online Publication, DOI: 10.1038 /nature09093). While representing a corner stone in the development of new quantum based technologies, these results are also fundamental for the understanding of how the quantum behaviour of single atoms can be controlled with light.
