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arXiv · 1508.04004

Independence of Optical Absorption on Auger Ionization in Single-Walled Carbon Nanotubes Revealed by Ultrafast e-h Photodoping

Mitchell D. Anderson·Meghan N. Beattie·Jack A. Alexander-Webber·Robin J. Nicholas·James M. Fraser
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Abstract

Auger-ionized carriers in a one-dimensional semiconductor are predicted to result in a strong band-gap renormalization. Isolated single-walled carbon nanotubes (SWCNT) under high-intensity laser irradiation exhibit strong nonlinear photoluminescence (PL) due to exciton-exciton annihilation (EEA). The presence of exciton disassociation during the rapid Auger-ionization caused by EEA would lead to a strong nonlinear absorption. By simultaneously measuring SWCNT PL and optical absorption of isolated SWCNT clusters in the PL saturation regime, we give evidence that Auger-ionized excitons do not disassociate but remain bound.

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Mitchell D. Anderson, Meghan N. Beattie, Jack A. Alexander-Webber, Robin J. Nicholas, James M. Fraser. 2015-08-17. Independence of Optical Absorption on Auger Ionization in Single-Walled Carbon Nanotubes Revealed by Ultrafast e-h Photodoping. https://doi.org/10.1088/1367-2630/18/2/023051

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