Quantum Many Body Theory

Our research activity deals with theoretical investigations and numerical simulations of materials in which strong correlations play an important role. These cannot be described in terms of standard electronic structure techniques based on effective single-electron theories.

We are particularly interested in situations in which these systems are driven out of thermodynamic equilibrium for example by a bias voltage, a thermal gradient or a periodic electromagnetic field.

A major activity of the group concerns the development and extension of new numerical approaches to treat these systems. These are based on nonequilibrium Green's functions techniques combined with master equation approaches, on exact diagonalisation in many-body Hilbert spaces, on matrix-product states and on cluster-embedding methods.

On the other hand, we apply theses approaches to investigate and predict transport and spectral properties of nonequilibrium correlated systems such as quantum dots, correlated interfaces and heterostructures, ultracold atoms, single-molecule transistors, as well as protoype photoelectric devices based on oxide heterostructures.