Voltage and Length-Dependent Phase Diagram of the Electronic Transport in Carbon Nanotubes

Abstract

In this work, we report experimental data on the evolution of the resistance with applied voltage in nonsuspended single-walled carbon nanotubes (SWNTs) of lengths ranging from 100 nm up to 6 microm. At low bias, the differential resistance as a function of length is well described by a linear fitting. At high biases, this magnitude first saturates and then decreases for nanotubes longer than 1 microm. We also present Monte Carlo numerical simulations for the one-dimensional Boltzmann's equation, describing how the electrons propagate along the tube and how they interact with acoustic and optical phonons. Our theoretical results show a remarkable agreement with the experimental differential resistance, allowing us to give a detailed description of the electron distribution function and the chemical potential along the nanotube. Finally, we present experimental results on the transition from Anderson localization at low bias to high diffusive regime at high bias in defected SWNTs. This result is combined with those of defect-free SWNTs to present a general landscape of the electronic transport in carbon nanotubes.