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تسجيل مستخدم جديدConductance in multiwall carbon nanotubes and semiconductor nanowires : evidence of a universal tunneling barrier
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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 $alpha$. A universal behavior as a function of $alpha$ 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 $Omega$ and a Thouless energy of about 40 meV exists for all samples.
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