Type:
Journal
Description:
The assessment of the presence and the origin of an intrinsic internal electric field in novel colloidal CdSe/CdS nanoheterostructures is of fundamental importance in order to understand their optical properties, due to both their impact on the basic research fields, and their potential in technological applications. To this aim, a deep study of the carrier dynamics in spherical (quantum dots) and rod-shaped (nanorods) colloidal seeded grown CdSe/CdS nanocrystals via time-resolved photoluminescence spectroscopy has been carried out in this report. A transient, power-dependent redshift of the spectra is observed. An optical nonlinearity is also found by continuous-wave photoluminescence measurements on ensemble and single nanostructures, which is attributed to a photoinduced screening of an internal field. This internal field could originate from the intrinsic piezoelectric polarization, which is a typical effect in …
Publisher:
American Physical Society
Publication date:
13 Nov 2008
Biblio References:
Volume: 78 Issue: 19 Pages: 195313
Origin:
Physical Review B