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Exciton resonances quench the photoluminescence of zigzag carbon nanotubes

Stephanie Reich·Christian Thomsen·John Robertson
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Abstract

We show that the photoluminescence intensity of single-walled carbon nanotubes is much stronger in tubes with large chiral angles - armchair tubes - because exciton resonances make the luminescence of zigzag tubes intrinsically weak. This exciton-exciton resonance depends on the electronic structure of the tubes and is found more often in nanotubes of the +1 family. Armchair tubes do not necessarily grow preferentially with present growth techniques; they just have stronger luminescence. Our analysis allows to normalize photoluminescence intensities and find the abundance of nanotube chiralities in macroscopic samples.

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Stephanie Reich, Christian Thomsen, John Robertson. 2005-04-23. Exciton resonances quench the photoluminescence of zigzag carbon nanotubes. https://doi.org/10.1103/physrevlett.95.077402

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