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arXiv · 1112.2439

Regularities of intermittent luminescence from spherical and tetrapod-shaped quantum dots

A. G. Vitukhnovsky·M. M. Kovalev·V. V. Lidsky·E. M. Khokhlov
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Abstract

Intermittent photoluminescence of colloidal core/shell semiconductor nanocrystals of spherical and branched shape was studied under CW-laser excitation. Luminescent multichannel registration system was applied for the fluorescence detection of single quantum dots (QDs) in the polystyrene matrix. Comparative statistical data were obtained and analyzed for nano-sphere CdSe/CdS and nano-tetrapod CdTe/CdSe crystals. It was found that "on-" and "off-" blinking times are distributed according to the power law both for spherical CdSe/CdS and tetrapod shape CdTe/CdSe samples in spite of significant QD formfactor differences. We have also found that regardless of the QD-shape both successive "on"-times and successive "off "-times are correlated and pointing out to the memory effect in the mechanism of QD re-emission comprising the prehistory of exciton birth and recombination. Pearson-s co-efficients were calculated for the correlations of QD-luminescence behavior. Results of experimental measurements were compared with the peculiarities of relevant phe-nomenon models proposed to date. The data obtained can be used for development of nanophotonic applications and nanocomposite light-emitting materials

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A. G. Vitukhnovsky, M. M. Kovalev, V. V. Lidsky, E. M. Khokhlov. 2011-12-12. Regularities of intermittent luminescence from spherical and tetrapod-shaped quantum dots. https://arxiv.org/abs/1112.2439

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