Rydberg Molecules for Ultracold Ion-Atom Scattering

In this thesis, a novel experimental method to enter the so far unexplored ultracold ion-atom scattering regime with the help of Rydberg molecules is proposed and theoretically exemplified with the lithium ion-atom system. In addition, the experimental proof-of-principle demonstration of two important aspects of the proposed method is presented, namely the production of low-energy ions from Rydberg atoms via an innovative V-type photoionization scheme and the effective compensation of electric stray fields with the help of the produced ions. Furthermore, the design and realization of a new ultracold rubidium-lithium Rydberg experiment with high resolution time- and position-sensitive single ion detection is described. To enable the highly spatially resolved ion detection, the new experiment comprises a sophisticated self-developed electrostatic ion microscope that provides a magnification of above 1000. The new experiment will allow for the complete realization of the proposed experimental method to study ultracold ion-atom scattering with the help of Rydberg molecules. Besides, it will enable the experimental investigation of a wide range of further fascinating phenomena such as, for example, the study of transport phenomena of single ultracold ion impurities in dense atomic quantum gases or the observation of spatial correlation formation in ultracold Rydberg gases.