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arXiv · 1502.05964

Influences of Exciton Diffusion and Exciton-Exciton Annihilation on Photon Emission Statistics of Carbon Nanotubes

Xuedan Ma·Oleskiy Roslyak·Juan G. Duque·Xiaoying Pang·Stephen K. Doorn·Andrei Piryatinski·David H. Dunlap·Han Htoon
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Abstract

Pump-dependent photoluminescence imaging and 2nd order photon correlation studies have been performed on individual single-walled carbon nanotubes (SWCNTs) at room temperature that enable the extraction of both the exciton diffusion constant and the Auger recombination coefficient. A linear correlation between these is attributed to the effect of environmental disorder in setting the exciton mean free-path and capture-limited Auger recombination at this lengthscale. A suppression of photon antibunching is attributed to creation of multiple spatially non-overlapping excitons in SWCNTs whose diffusion length is shorter than the laser spot size. We conclude that complete antibunching at room temperature requires an enhancement of exciton-exciton annihilation rate that may become realizable in SWCNTs allowing for strong exciton localization.

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Xuedan Ma, Oleskiy Roslyak, Juan G. Duque, Xiaoying Pang, Stephen K. Doorn, Andrei Piryatinski, David H. Dunlap, Han Htoon. 2015-02-20. Influences of Exciton Diffusion and Exciton-Exciton Annihilation on Photon Emission Statistics of Carbon Nanotubes. https://doi.org/10.1103/physrevlett.115.017401

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