Scattering strength of potassium on a carbon nanotube with known chirality

TL;DR

This study measures how potassium impurities affect charge transport in a specific carbon nanotube, revealing that holes are scattered much more efficiently than electrons, which aids in designing nanotube sensors.

Contribution

It provides the first detailed measurement of potassium scattering strength on a known-chirality nanotube, elucidating the scattering potential's spatial characteristics.

Findings

Holes are scattered 37 times more efficiently than electrons by potassium.

The scattering strength helps understand adsorbate-induced scattering mechanisms.

Results inform the design of nanotube-based sensors.

Abstract

We have measured the scattering strength of charged impurities on a semiconducting single-walled carbon nanotube with known chirality. The resistivity of the nanotube is measured as a function of the density of adsorbed potassium atoms, enabling the determination of the resistance added by an individual potassium atom. Holes are scattered 37 times more efficiently than electrons by an adsorbed potassium atom. The determined scattering strength is used to reveal the spatial extent and depth of the scattering potential for potassium, a model Coulomb adsorbate. Our result represents an essential experimental input to understand adsorbate-induced scattering and provides a crucial step for paving the way to rational design of nanotube-based sensors.