3.2 Solids and Nanostructures: Electrons, Spins, and Phonons

In this project we investigate ultrafast and nonlinear phenomena in solids and nanostructures. Both fundamental questions of basic research and current questions of applied research are addressed.

The core vision of Project 3.2 is to improve our understanding of many-body physics from first principles and to gain control over fundamental quantum degrees of freedom, such as spin, orbital angular momentum, polarization, and valley indices, in solids and nanostructures by applying light-driven excitation techniques. We pursue a comprehensive microscopic characterization of quantum materials of extremely high spectral purities and of laser-induced transient states at their intrinsic time and length scales, with the dual  objective of advancing fundamental understanding and identifying pathways to exploit these non-equilibrium phenomena in future technologies that combine novel functionalities with enhanced energy efficiency. To this end, we continue to develop a unique and versatile set of spectroscopic techniques that span a broad spectral range from terahertz to soft X-rays achieving either high temporal resolution down to the attosecond time scale in pump-probe experiments or high spectral resolution and precision through novel schemes of frequency-comb spectroscopy. These efforts are guided and complemented by state-of-the-art time-dependent density functional theory and theoretical optics for the description of light-matter interaction and light propagation in solids and nanostructures.