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arXiv · 2103.15477

Diffusive and Unimolecular Nonradiative Decay of Excited States in Doped Carbon Nanotubes

Klaus H. Eckstein·Pascal Kunkel·Markus Voelckel·Friedrich Schöppler·Abasi Abudulimu·Larry Lüer·Tobias Hertel
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Abstract

Doping can profoundly affect the electronic- and optical-structure of semiconductors. Here we address the effect of surplus charges on non-radiative (NR) exciton and trion decay in doped semiconducting single-wall carbon nanotubes. The dependence of exciton photoluminescence quantum yields and exciton decay on the doping level, with its characteristically stretched-exponential kinetics, is attributed to diffusion-limited NR decay at charged impurity sites. By contrast, trion decay is unimolecular with a rate constant of $2.0\,\rm ps^{-1}$. Our experiments thus show that charged impurities not only trap trions and scavenge mobile excitons but that they also facilitate efficient NR energy dissipation for both.

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Klaus H. Eckstein, Pascal Kunkel, Markus Voelckel, Friedrich Schöppler, Abasi Abudulimu, Larry Lüer, Tobias Hertel. 2021-03-29. Diffusive and Unimolecular Nonradiative Decay of Excited States in Doped Carbon Nanotubes. https://arxiv.org/abs/2103.15477

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