From Single Atoms to Engineered “Super-Atoms”: Interfacing Photons and Atoms in Free Space

Abstract

During the last decades the development of laser cooling and trapping has revolutionized the field of quantum optics. Now we master techniques to control the quantum properties of atoms and light, even at a single atom and single photon level. Understanding and controlling interactions of atoms and light both on the microscopic single particle and on the macroscopic collective levels, are two of the very active directions of the current research in this field. The goal is to engineer quantum systems with tailored properties designed for specific applications. One of the ambitious applications on this way is interfacing quantum information for quantum communication and quantum computing. We summarize here theoretical ideas and experimental methods for interfacing atom-based quantum memories with single flying photons.

Ground state excitation of an atom strongly coupled to a free quantum field

“…One can even design 'superatoms' to scale up the coupling strength. (See [29,30] for a review of this topic.) Recently Paris et al [31] reported on the realization of coherent coupling between a propagating few-photon optical field and a single Rydberg superatom in free space.…”