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arXiv · 1002.4102

Photodarkening of blinking quantum dots is not governed by Auger recombination

Shamir Rosen·Osip Schwartz·Dan Oron
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Abstract

The observed intermittent light emission from colloidal semiconductor nanocrystals has long been associated with Auger recombination assisted quenching. We test this view by observing transient emission dynamics of CdSe/CdS/ZnS semiconductor nanocrystals using time-resolved photon counting. The size and intensity dependence of the observed decay dynamics are inconsistent with the those expected from Auger processes. Moreover, the data suggests that in the `off' state the quantum dot cycles in a three-step process: photoexcitation, rapid trapping and subsequent slow nonradiative decay.

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Shamir Rosen, Osip Schwartz, Dan Oron. 2010-02-22. Photodarkening of blinking quantum dots is not governed by Auger recombination. https://arxiv.org/abs/1002.4102

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