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Quantum Conductance Steps in Solutions of Multiwalled Carbon Nanotubes

A. Urbina·I. Echeverría·A. Pérez-Garrido·A. Díaz-Sánchez·J. Abellán
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Abstract

We have prepared solutions of multiwalled carbon nanotubes in Aroclor 1254, a mixture of polychlorinated biphenyls. The solutions are stable at room temperature. Transport measurements were performed using a scanning--tunneling probe on a sample prepared by spin--coating of the solution on gold substrates. Conductance steps were clearly seen. An histogram of a high number of traces shows maximum peaks at integer values of the conductance quantum $G_0 = 2e^2/h$, demonstrating ballistic transport at room temperature along the carbon nanotube over distances longer than $1.4μm$.

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A. Urbina, I. Echeverría, A. Pérez-Garrido, A. Díaz-Sánchez, J. Abellán. 2003-05-12. Quantum Conductance Steps in Solutions of Multiwalled Carbon Nanotubes. https://doi.org/10.1103/physrevlett.90.106603

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