TY - GEN UR - https://archiv.ub.uni-heidelberg.de/volltextserver/30661/ N2 - Rydberg electromagnetically induced transparency (Rydberg EIT) enables extremely strong optical nonlinearities, opening the possibility for photon-photon interactions and exotic states of light. Subjects of this thesis are the development and the experimental test of semiclassical models for Rydberg EIT systems on two-photon resonance. Beyond that, this thesis opens the route towards enhanced photon-photon interactions in terms of an increased interaction time. Three major results are achieved: (i) In the semiclassical regime, we extend existing models and reveal that a two-body, two-photon resonance leads to an enhanced nonlinear optical response. (ii) We develop an experimental method to rigorously test semiclassical models of Rydberg EIT. For this purpose, we go beyond previous experimental investigations and measure transmission spectra on two-photon resonance, where the linear response of the system vanishes. We identify qualitative differences between a measured absorption feature and predictions provided by a mean-field model, a Monte-Carlo rate equation simulation, and a theory based on a pairwise treatment of atomic interactions. (iii) In the quantum regime, we propose and analyze a novel scheme to endow a stationary light polariton with a Rydberg character, resulting in a stationary Rydberg polariton. Our scheme offers the prospect for polariton interactions with increased interaction time, and thus might find application in the creation of exotic states of light. CY - Heidelberg A1 - Tebben, Annika AV - public TI - Rydberg Electromagnetically Induced Transparency - A vanishing linear response, resonances, and a stationary Rydberg polariton ID - heidok30661 Y1 - 2021/// ER -