Storage Ring-Based Inverse Compton X-Ray Sources: Cavity Design, Beamline Development and X-Ray Applications

This thesis presents research on novel laboratory-scale synchrotron X-ray sources based on inverse Compton scattering and applications of their X-ray radiation using the Munich Compact Light Source (MuCLS) as an example. It provides an introduction to the theory of this laser-electron interaction, laser resonators and X-ray interactions with matter. On this basis, upgrades to the laser system including the development of a new laser optic, X-ray beam stabilisation and two techniques for fast X-ray energy switching of inverse Compton sources are presented. On the application side, the beamline, designed and developed for the inverse Compton X-ray source at the MuCLS, is described before various techniques and applications are demonstrated at this laboratory-scale synchrotron X-ray facility. Among them are K-edge subtraction imaging, X-ray phase contrast imaging and X-ray absorption spectroscopy. Additionally, a new X-ray microscopy technique, called full-field structured-illuminationsuper-resolution X-ray transmission microscopy, is presented.

Apart from research conducted at the MuCLS, this thesis contains an in-depth overview on the state of the art of the various types of inverse Compton X-ray sources that have been realised so far. Accordingly, this thesis may serve as a guide and reference work for researchers working with inverse Compton X-ray sources as well as future users of such devices.

Benedikt Sebastian Günther has been working on inverse Compton X-ray sources and their applications since 2015. He received his Bachelor of Science and Master of Science in Physics from the Technical University of Munich (TUM) in 2011 and 2014, respectively. After his graduation, he joined the Sentech GmbH, where he worked on ellipsometry. In 2015, he returned to the Technical University of Munich for pursuing his PhD on the topic of inverse Compton X-ray sources and their applications. His doctorate included a six month research stay at Lyncean Technologies Inc., a company developing inverse Compton X-ray sources. In Dezember 2021, he was awarded his PhD in Physics. Now he is a postdoctoral research fellow at the Technical University of Munich.