Correlated and X-Ray Quantum Dynamics


Quantum optical concepts based on coherence and interference have proven extremely successful for the study and manipulation of atoms and molecules. Recent improvements in modern x-ray light sources prompt the question, whether such techniques could also be applied in the hard x-ray regime. This could not only pave the way for new applications, but also is indispensable for taking advantage of the full potential of these new machines.

However, despite the new light sources, it remains challenging to exploit quantum optical phenomena in the x-ray domain, and it is typically not possible to directly transfer established concepts to the x-ray domain. We develop new approaches to establish quantum optical methods at x-ray energies, focusing in particular on the coupling of x-rays to nuclear resonances in large ensembles of Mössbauer nuclei. While we mainly work theoretically, we regularly conduct experiments at x-ray sources in collaboration with other groups to explore new regimes and to verify our predictions.

Interestingly, the relevant setups in x-ray quantum optics typically involve strong collective phenomena inducing correlations within the ensemble of nuclei, and the understanding or even control of these phenomena is a key requirement. Motivated by this, we also study correlations and collective phenomena in other related model systems, as well as fundamental coherence and interference effects.