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Quantum Conductance Steps in Solutions of Multiwalled Carbon Nanotubes

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 نشر من قبل Diaz-Sanchez Anastasio
 تاريخ النشر 2003
  مجال البحث فيزياء
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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 $1.4mu m$.



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