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arXiv · 0909.1920

Anomalous temperature dependence of the the spin-flip thermalization time between the dark and bright exciton states in silicon nanocrystals

Brian Julsgaard·Ying-Wei Lu·Peter Balling·Arne Nylandsted Larsen
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Abstract

Silicon nanocrystals are studied by time-resolved fluorescence spectroscopy. After laser excitation the bright and dark exciton ground state levels are populated at random, but subsequently the decay curves reveal a thermalization between these levels. The characteristic thermalization time is found to be approximately 100 ns for temperatures below 100 K and surprisingly increases for higher temperatures. The decay curves are analyzed using a simple two-state model for the bright and dark exciton ground states.

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Brian Julsgaard, Ying-Wei Lu, Peter Balling, Arne Nylandsted Larsen. 2009-09-10. Anomalous temperature dependence of the the spin-flip thermalization time between the dark and bright exciton states in silicon nanocrystals. https://arxiv.org/abs/0909.1920

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