Absorption imaging of a single atom

• Published in: Nature communications 2012-07, Vol.3 (1), p.933-933, Article 933
• Main Authors: Streed, Erik W., Jechow, Andreas, Norton, Benjamin G., Kielpinski, David
• Format: Article
• Language: English
• Subjects: 639/624/1107/510; 639/766/36; Humanities and Social Sciences; multidisciplinary; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms1944

Absorption imaging has played a key role in the advancement of science from van Leeuwenhoek's discovery of red blood cells to modern observations of dust clouds in stellar nebulas and Bose–Einstein condensates. Here we show the first absorption imaging of a single atom isolated in a vacuum. The optical properties of atoms are thoroughly understood, so a single atom is an ideal system for testing the limits of absorption imaging. A single atomic ion was confined in an RF Paul trap and the absorption imaged at near wavelength resolution with a phase Fresnel lens. The observed image contrast of 3.1 (3)% is the maximum theoretically allowed for the imaging resolution of our set-up. The absorption of photons by single atoms is of immediate interest for quantum information processing. Our results also point out new opportunities in imaging of light-sensitive samples both in the optical and X-ray regimes. Absorption imaging relies on the capture of photons by an object to create intensity contrasts, allowing for the visualization of small quantum systems. Streed et al . demonstrate the first absorption imaging of an isolated ytterbium ion, with contrast at the limit of semiclassical theory.