We calculate optical and electronic and quantum optical properties of different material systems, in particular semiconductor nanostructures. For example, situations are analyzed in which matter is excited by very short laser pulses. This makes it possible to investigate in detail very rapid dynamic processes that take place on time scales of a few femtoseconds (1 fs = 10-15 s). The interaction with very intense light pulses can drastically alter the optical properties, e.g., modify transition frequencies and enable new excitation paths. In addition to purely optical processes, also optically-induced transport phenomena such as photocurrents, Bloch oscillations, etc. are investigated.
The analysis of these questions typically requires the solution of high-dimensional systems of coupled dynamic equations. This is usually only possible numerically. Therefore, programs are developed and evaluated on PCs and parallel clusters to obtain useful results.