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arXiv · 1001.4546

Excitons and high-order optical transitions in individual carbon nanotubes

Stephane Berciaud·Christophe Voisin·Hugen Yan·Bhupesh Chandra·Robert Caldwell·Yuyao Shan·Louis E. Brus·James Hone·Tony F. Heinz
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Abstract

We examine the excitonic nature of high-lying optical transitions in single-walled carbon nanotubes by means of Rayleigh scattering spectroscopy. A careful analysis of the principal transitions of individual semiconducting and metallic nanotubes reveals that in both cases the lineshape is consistent with an excitonic model, but not one of free-carriers. For semiconducting species, side-bands are observed at ~200 meV above the third and fourth optical transitions. These features are ascribed to exciton-phonon bound states. Such side-bands are not apparent for metallic nanotubes,as expected from the reduced strength of excitonic interactions in these systems.

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Stephane Berciaud, Christophe Voisin, Hugen Yan, Bhupesh Chandra, Robert Caldwell, Yuyao Shan, Louis E. Brus, James Hone, Tony F. Heinz. 2010-01-25. Excitons and high-order optical transitions in individual carbon nanotubes. https://doi.org/10.1103/physrevb.81.041414

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