Structure and ultrafast dynamics of white-light-emitting CdSe nanocrystals

The first images of the structure of white-light emitting ultrasmall CdSe nanocrystals are obtained by using aberration-corrected atomic number contrast scanning transmission electron microscopy (Z-STEM). The exciton dynamics are measured at different wavelengths of the white-light spectrum by using ultrafast fluorescence upconversion spectroscopy, which has suggested that a myriad of trap states are responsible for the broad-spectrum emission.