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arXiv · cond-mat/0511585

Tuning the conductance of single-walled carbon nanotubes by ion irradiation in the Anderson localization regime

Abstract

Carbon nanotubes are a good realization of one-dimensional crystals where basic science and potential nanodevice applications merge. Defects are known to modify the electrical resistance of carbon nanotubes. They can be present in as-grown carbon nanotubes, but controlling externally their density opens a path towards the tuning of the nanotube electronic characteristics. In this work consecutive Ar+ irradiation doses are applied to single-walled nanotubes (SWNTs) producing a uniform density of defects. After each dose, the room temperature resistance versus SWNT-length [R(L)] along the nanotube is measured. Our data show an exponential dependence of R(L) indicating that the system is within the strong Anderson localization regime. Theoretical simulations demonstrate that mainly di-vacancies contribute to the resistance increase induced by irradiation and that just a 0.03% of di-vacancies produces an increase of three orders of magnitude in the resistance of a 400 nm SWNT length.

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C. Gomez-Navarro, P. J. De Pablo, J. Gomez-Herrero, B. Biel, F. J. Garcia-Vidal, A. Rubio, F. Flores. 2005-11-23. Tuning the conductance of single-walled carbon nanotubes by ion irradiation in the Anderson localization regime. https://doi.org/10.1038/nmat1414

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