Related Experiment Video
Updated: Jul 6, 2026
Compact Quantum Dots for Single-molecule Imaging
Published on: October 9, 2012
On the absence of detectable carrier multiplication in a transient absorption study of InAs/CdSe/ZnSe
Meirav Ben-Lulu1, David Mocatta, Mischa Bonn
1Institute of Chemistry, the Farkas Center for Light Induced Processes, and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
Abstract:
Tunable femtosecond pump-near IR probe measurements on InAs/CdSe/ZnSe core/shell1/shell2 nanocrystal quantum dots were conducted to quantify spontaneous carrier multiplication previously reported in this system. Experimental conditions were chosen to eliminate the need for determining absolute wavelength dependent cross sections of the nanocrystals and allow direct comparison of band edge absorption bleach kinetics for different excitation energies up to 3.7 times the band gap. Results for two sample sizes show no signs of carrier multiplication within that range. This result is discussed in light of reports describing occurrence of this novel phenomenon in quantum dots based on this as well as numerous other semiconductor materials.
