Ruprecht-Karls-University Heidelberg
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The Group is moving to the newly founded Center for Optical Quantum Technologies at the University of Hamburg: Phd and postdoc positions are available

Atoms, Molecules and Mesoscopic Systems in External Fields

Our research covers a broad range of topics concerning the structure and behaviour of microscopic as well as mesoscopic systems in external fields. External magnetic, electric or electromagnetic fields represent distinct tools to influence, shape or control the structure and dynamics of microscopic or mesoscopic systems. Atomic systems that are highly excited, so-called Rydberg atoms, are very susceptible to external fields and deform easily. As a result unexpected structures and novel phenomena emerge that possess no counterparts in field-free space. Examples herefore are the intrisically driven classical diffusion of atoms in magnetic fields, the self-ionization effect or the giant dipole states in crossed electric and magnetic fields, which are currently of major interest in the context of the formation of antihydrogen. The formation process and the mere existence of negative ions form is deeply altered in the presence of magnetic fields. For cosmic laboratories, such as the atmospheres of magnetic white dwarfs, our knowledge on the atomic properties in strong fields is a key ingredient for the identification of these objects.

Turning from atoms to molecules it is obvious that the binding and consequently structure, as well as the dynamics and therefore chemical reaction properties, are severely modified in the presence of external fields. This holds in particular in the ultracold regime, where the collisional energy is extremely small and any perturbing external force induces major changes in the collision process. Beyond changing the properties of individual systems or their binary reactions the classical or quantum transport of ensembles is altered equally in the presence of fields.

See also the theory group "Ultracold Atomic and Molecular Systems".