OIST Centre for Quantum Technologies Colloquium

AN ION MEETS A RYDBERG ATOM

Abstract:

We report on our recent studies on ion-Rydberg atom interactions performed in the ultra-cold quantum regime, using a high-resolution ion microscope. This apparatus provides temporal and spatial resolved images of charged particles with a resolution down to 200nm. The interaction between an ion and a Rydberg atom leads to a rich structure of pair potentials, which can be used to study molecular states as well collisional dynamics. The ion induces a stark splitting in the Rydberg atom, which leads at small distances to a manifold of avoided crossing. If the potential curves feature a local minimum it is possible to photo-associate molecules. With the help of our ion microscope we can take spatially resolved images of the emerging dimer. When kicking one of the atoms it is even possible to observe molecular vibrations in real space. In a second experiment we focused on the collision dynamics of a Rydberg atom and an ion. Due the complexity of the pair states and the large number of avoided crosses we can observe a sequence of diabatic and adiabatic transition during the collision.

Biography:

Robert Loew studied physics from 1994 to 2000 at the University of Regensburg (Germany), Wesleyan University (USA), University of Bonn (Germany) and MIT (USA). In the following years he earned his PhD with experimental studies on ultracold Rydberg atoms in the group of Tilman Pfau at the University of Stuttgart (Germany). Since 2006 he is a permanent researcher in Stuttgart. Besides his research on hot and cold atomic vapours, he is also very active in various outreach activities as well in writing books for a general audience.