Femtosecond polarization relaxation in CdSe nanocrystals

We present ultrafast pump-probe studies on chem. prepd. CdSe nanocrystals. Upon pulsed optical excitation we find pronounced oscillations, indicating strong coupling to a LO phonon mode. From the polarization dependence of the signal addnl. information about the very first coherent events of exciton dynamics is obtained. The obsd. anisotropy behavior suggests strongly driven dynamics and rapid coherent motion. [on SciFinder (R)