Physics – Condensed Matter – Materials Science
Scientific paper
2008-06-11
Physics
Condensed Matter
Materials Science
10 pages, 7 figures
Scientific paper
10.1103/PhysRevB.78.125325
We report here an assessment of carrier multiplication (CM) yields in PbSe and PbS nanocrystals (NCs) by a quantitative analysis of biexciton and exciton dynamics in transient photoluminescence decays. Interest in CM, the generation of more than one electron and hole in a semiconductor after absorption of one photon, has renewed in recent years because of reports suggesting greatly increased efficiencies in nanocrystalline materials compared to the bulk form, in which CM was otherwise too weak to be of consequence in photovoltaic energy conversion devices. In our PbSe and PbS NC samples, however, we estimate using transient photoluminescence that at most 0.25 additional e-h pairs are generated per photon even at energies hv > 5Eg, instead of the much higher values reported in the literature. We argue by comparing NC CM estimates and reported bulk values on an absolute energy basis, which we justify as appropriate on physical grounds, that the data reported thus far are inconclusive with respect to the importance of nanoscale-specific phenomena in the CM process.
Bawendi Moungi G.
Chang L. Y. L.
Geyer Scott M.
Nair Gautham
No associations
LandOfFree
Carrier multiplication yields in PbS and PbSe nanocrystals measured by transient photoluminescence does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Carrier multiplication yields in PbS and PbSe nanocrystals measured by transient photoluminescence, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Carrier multiplication yields in PbS and PbSe nanocrystals measured by transient photoluminescence will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-689851