Abstract
Nondegenerate four wave mixing (NDFWM) has been proven to be a useful tool to investigate femtosecond phase relaxation processes in II-VI quantum dots. The range of application covers dephasing times between 10 fs and some picoseconds. By means of NDFWM the intensity- and temperature-dependent dephasing has been studied in CdS quantum dots with radii larger than the Bohr radius.