Theory of Correlated Systems out of Equilibrium
We study the nonequilibrium dynamics of interacting quantum many-particle systems, such as correlated electrons, phonons and spins under the influence of external driving forces, from a microscopic perspective. For this purpose we will use dynamical mean-field theory (DMFT) and its extensions, which solve quantum lattice models in the thermodynamic limit by mapping them onto a small cluster embedded in an effective medium.
A crucial part of our research is the development of efficient numerical techniques to compute the real-time evolution in those impurity models, using Quantum Monte Carlo, diagrammatic techniques, and exact diagonalization. Our goal is to transform DMFT and its extensions into a predictive tool for the nonequilibrium dynamics in correlated systems, and to uncover new effects such as long-lived hidden phases that can be reached along non-thermal excitation pathways, driven steady states far from linear response, and dynamical phase transitions.