ISBN 978-3-8439-4916-3

978-3-8439-4916-3, Reihe Physik

Jan Kumlin
Collective Effects of Light-Matter Interactions in Rydberg Superatoms

244 Seiten, Dissertation Universität Stuttgart (2021), Softcover, A5

Zusammenfassung / Abstract

In this thesis we study collective effects in cold and ultracold atomic ensembles where the atoms interact via the long-range and anisotropic dipole-dipole interaction. These systems have gained a lot of interest both experimentally as well as theoretically over the past years thanks to the increasing experimental control and ability to manipulate these systems for example using external electric and magnetic fields.

The first and main part of this thesis deals with collective effects of light-matter interactions in Rydberg superatoms. It is by now a well-known fact that systems in which many emitters are coupled to a common radiation field show collective and cooperative behavior. A Rydberg superatom, which consists of many thousands of individual emitters and is converted into a single, macroscopic two-level system by the Rydberg blockade, represents a particularly interesting system for studying the interaction of light and matter. This thesis focusses on the influence of the resonant dipole-dipole interaction, which is mediated by propagating photons, on the microscopic, internal dynamics of such a Rydberg superatom.

The second part of this thesis deals with quantum effects in dipolar Bose gases. Recent experiments with ultracold lanthanide atoms which are characterized by a large magnetic moment have revealed the crucial importance of beyond-mean-field corrections in understanding the dynamics of the gas. Here, we study how the presence of an external optical lattice modifies the structure of those corrections.