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Effect of Number of Walls on Plasmon Behavior in Carbon Nanotubes

M. H. Upton·R. F. Klie·J. P. Hill·T. Gog·D. Casa·W. Ku·Y. Zhu·M. Y. Sfeir·J. Misewich·G. Eres·D. Lowndes
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Abstract

We investigate the physical parameters controlling the low energy screening in carbon nanotubes via electron energy loss spectroscopy and inelastic x-ray scattering. Two plasmon-like features are observed, one near 9 eV (the so-called pi plasmon) and one near 20 eV (the so-called pi+sigma plasmon). At large nanotube diameters, the pi+sigma plasmon energies are found to depend exclusively on the number of walls and not on the radius or chiral vector. The observed shift indicates a change in the strength of the screening and in the effective interaction at inter-atomic distances, and thus this result suggests a mechanism for tuning the properties of the nanotube.

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M. H. Upton, R. F. Klie, J. P. Hill, T. Gog, D. Casa, W. Ku, Y. Zhu, M. Y. Sfeir, J. Misewich, G. Eres, D. Lowndes. 2007-04-04. Effect of Number of Walls on Plasmon Behavior in Carbon Nanotubes. https://arxiv.org/abs/cond-mat/0611151

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