The present work deals with the theoretical and experimental study of optical Feshbach resonances with Rydberg molecules. It experimentally demonstrates a change in the interatomic interaction in the ultracold regime with the help of Rydberg molecular states. These peculiar molecules have sparked a whole new research area in the last couple of years, as their binding mechanism can not be classified in any of the standard chemical bonds. A perturbing atom is bound by a scattering interaction with a quasi free electron in a Rydberg state. These molecules, therefore, possess extraordinary properties in comparison with usual molecular states. The underlying experiment consists of an apparatus for producing ultracold quantum gases in combination with the possibility to excite and investigate Rydberg S-, P- and D-states.
