Quantum Conductance Steps in Solutions of Multiwalled Carbon Nanotubes

TL;DR

This study demonstrates room-temperature ballistic transport in multiwalled carbon nanotubes through conductance steps observed in solution-processed samples, indicating potential for nanoscale electronic applications.

Contribution

First to observe quantized conductance steps in solution-processed multiwalled carbon nanotubes at room temperature.

Findings

Conductance steps at integer multiples of G_0 observed

Ballistic transport over distances exceeding 1.4 micrometers

Stable solutions of nanotubes in Aroclor 1254 prepared

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 $1.4\mu m$.