- Assistant researcher University Frankfurt, 1967-1969, University Munich, 1969-1970, University Regensburg, 1970-1977. Professor University Stuttgart, since 1978. Visiting professor University Strasbourg, France, 1983, Arizona State University, Tempe, 1987, Santa Fe Institute, 1991, University Oregon, Eugene, 1997.
- Quantum Networks: Dynamics of Open Nanostructures
- Quantum Networks is focused on density matrix theory cast into a product operator representation, particularly adapted to describing networks of finite state subsystems.