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Hopping Conduction in Disordered Carbon Nanotubes

D. P. Wang·D. E. Feldman·B. R. Perkins·A. J. Yin·G. H. Wang·J. M. Xu·A. Zaslavsky
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Abstract

We report electrical transport measurements on individual disordered carbon nanotubes, grown catalytically in a nanoporous anodic aluminum oxide template. In both as-grown and annealed types of nanotubes, the low-field conductance shows as exp[-(T_{0}/T)^{1/2}] dependence on temperature T, suggesting that hopping conduction is the dominant transport mechanism, albeit with different disorder-related coefficients T_{0}. The field dependence of low-temperature conductance behaves an exp[-(xi_{0}/xi)^{1/2}] with high electric field xi at sufficiently low T. Finally, both annealed and unannealed nanotubes exhibit weak positive magnetoresistance at low T = 1.7 K. Comparison with theory indicates that our data are best explained by Coulomb-gap variable range hopping conduction and permits the extraction of disorder-dependent localization length and dielectric constant.

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D. P. Wang, D. E. Feldman, B. R. Perkins, A. J. Yin, G. H. Wang, J. M. Xu, A. Zaslavsky. 2006-10-26. Hopping Conduction in Disordered Carbon Nanotubes. https://doi.org/10.1016/j.ssc.2007.02.028

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