A marriage of atoms and ions

Appl. Phys. B http://dx.doi.org/10.1007/s00340-011-4726-6 (2011)

Credit: © 2011 SPRINGER

Scientists from the Raman Research Institute in India and the Johannes Gutenberg University in Germany have unveiled a device that can simultaneously trap both ions and cold atoms. The apparatus combines a linear radiofrequency Paul trap for ions with a six-laser-beam magneto-optical trap for atoms. Spatial overlap between the traps allows the investigation of ion–atom interactions at low temperatures. The researchers cooled the atoms by laser Doppler cooling using light from an amplified home-made external-cavity diode laser. They tested their design with ⁸⁵Rb atoms and ⁸⁵Rb⁺ ions, which were made by using two-photon ionization to strip electrons from ⁸⁵Rb atoms. The researchers say that the scheme also lends itself to any species that can be laser-cooled in a vapour cell, and that experiments with multiple species may even be possible.