Josephson photonics and Josephson scanning tunneling microscopy. Inelastic charge transfer across superconducting junctions

This thesis has presented seven publications in a comprehensive scientific context, which resulted from the author's research activities under the supervision of J. Ankerhold at the Institute for Complex Quantum Systems at Ulm University between December 2015 and May 2019. They are part of a very young subfield of mesoscopic physics in which the role of quantum optical phenomena in charge transport across tunnel junctions is investigated. The overriding goal with regard to basic research lies here in the understanding of fundamental processes of nonrelativistic quantum electrodynamics under nonequilibrium conditions. New insights into the quantum optics of mesoscopic conductors, however, are not only of fundamental scientific interest but have also led to the emergence of auspicious platforms for novel quantum devices in communication, information, and sensing technology.