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Conductance in multiwall carbon nanotubes and semiconductor nanowires : evidence of a universal tunneling barrier

J. -F. Dayen·X. Hoffer·T. L. Wade·M. Konczykowski·J. -E. Wegrowe
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Abstract

Electronic transport in multiwall carbon nanotubes and semiconductor nanowires was compared. In both cases, the non ohmic behavior of the conductance, the so-called zero bias anomaly, shows a temperature dependence that scales with the voltage dependence. This robust scaling law describes the conductance $G(V,T)$ by a single coefficient $α$. A universal behavior as a function of $α$ is found for all samples. Magnetoconductance measurements furthermore show that the conduction regime is weak localization. The observed behavior can be understood in terms of the coulomb blockade theory, providing that a unique tunnel resistance on the order of 2000 $Ω$ and a Thouless energy of about 40 meV exists for all samples.

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J. -F. Dayen, X. Hoffer, T. L. Wade, M. Konczykowski, J. -E. Wegrowe. 2004-12-13. Conductance in multiwall carbon nanotubes and semiconductor nanowires : evidence of a universal tunneling barrier. https://arxiv.org/abs/cond-mat/0412316

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