Phonon-Assisted Intertube Electronic Transport in an Armchair Carbon Nanotube Film

The electrical conductivity of a macroscopic assembly of nanomaterials is determined through a complex interplay of electronic transport within and between constituent nano-objects. Phonons play dual roles in this situation: their increased populations tend to reduce the conductivity via electron scattering, while they can boost the conductivity by assisting electrons to propagate through the potential-energy landscape. We identified a phonon-assisted coherent electron transport process between neighboring nanotubes in temperature-dependent conductivity measurements on a macroscopic film of armchair single-wall carbon nanotubes. Through atomistic modeling of electronic states and calculations of both electronic and phonon-assisted junction conductances, we conclude that phonon-assisted conductance is the dominant mechanism for observed high-temperature transport in armchair carbon nanotubes. The unambiguous manifestation of coherent intertube dynamics proves a single-chirality armchair nanotube film to be a unique macroscopic solid-state ensemble of nano-objects promising for the development of room-temperature coherent electronic devices.

Automated summary

The electrical conductivity of macroscopic assemblies of nanomaterials is determined by the interplay between electronic transport and phonons. Phonons can reduce conductivity through electron scattering, but also enhance it by aiding electron propagation. In this study, we found that phonon-assisted coherent electron transport is the dominant mechanism for high-temperature transport in carbon nanotubes. This discovery proves the potential of single-chirality carbon nanotube films as unique solid-state ensembles for the development of room-temperature coherent electronic devices.