Regensburg 2010 – wissenschaftliches Programm
HL 60.29: Poster
Donnerstag, 25. März 2010, 18:00–20:00, Poster D1
Photoluminescence of extremely dilute semiconductor nanoparticle films — •Matthias Offer1, Martin Geller1, Axel Lorke1, and Hartmut Wiggers2 — 1Experimental Physics and CeNIDE, University Duisburg-Essen — 2IVG and CeNIDE, University Duisburg-Essen
Light-emitting silicon nanoparticles are attractive candidates for future optoelectronic applications due to ther visible photoluminescence with an efficiency, that is several orders of magnitude higher than for bulk Si. To realize of such devices, a detailed knowledge of the recombination dynamics is an important prerequisite. The photoluminescence (PL) of silicon nanoparticles exhibits an interesting exitonic fine structure with a bright and a dark state, which, surprisingly, have very similar radiative recombination lifetimes . To elucidate the intriguing excitonic properties of Si nanoparticles, it is highly desirable to investigate single particles or few-particle ensembles to answer questions regarding homogeneous line broadening and Zeeman shift. We have dispersed Si nanoparticles in toluene with 1% PMMA, which makes it possible to deposit extremely dilute films of Si particles on arbitrary surfaces. As a reference system, we prepared a similar dispersion with CdSe nanoparticles. Furthermore, a scanning micro-PL setup was designed and realized to map out the local optical properties of nanoscopic semiconductor structures. First results of spatially resolved PL on nanoparticles will be presented and compared to spectra of large-scale ensembles.
 S. Luettjohann et al., Europhys. Lett. 79, 37002 (2007)