An atom in open space can be detected by means of resonant absorption and reemission of electromagnetic waves, known as resonance fluorescence, which is a fundamental phenomenon of quantum optics. We report on the observation of scattering of propagating waves by a single artificial atom. The behavior of the artificial atom, a superconducting macroscopic two-level system, is in a quantitative agreement with the predictions of quantum optics for a pointlike scatterer interacting with the electromagnetic field in one-dimensional open space. The strong atom-field interaction as revealed in a high degree of extinction of propagating waves will allow applications of controllable artificial atoms in quantum optics and photonics.
@article{arxiv.1002.4944,
title = {Resonance Fluorescence of a Single Artificial Atom},
author = {O. Astafiev and A. M. Zagoskin and A. A. Abdumalikov and Yu. A. Pashkin and T. Yamamoto and K. Inomata and Y. Nakamura and J. S. Tsai},
journal= {arXiv preprint arXiv:1002.4944},
year = {2015}
}