We use femtosecond time-resolved transmission spectroscopy to study the density and time dependence of transient absorption changes of CdSe nanocrystals. Our data show pronounced absorption saturation up to complete bleaching of the lowest optical transition. At high carrier density the nonlinear spectra show several peaks that can be related to the two lowest quantized electron states. Thetime dependence of the carrier-induced absorption changes indicates an ultrafast relaxation process within the strongly broadened absorption lines.
|Number of pages||8|
|Journal||Applied Physics B: Lasers and Optics|
|Publication status||Published - Jan 1996|
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)
- Atomic and Molecular Physics, and Optics