Conductance through a single impurity in the metallic zigzag carbon nanotube

TL;DR

This paper studies how a single impurity affects electrical conductance in metallic zigzag carbon nanotubes, revealing complex behaviors like resonant scattering and tunneling influenced by impurity strength and bias voltage.

Contribution

It uncovers the interplay between scattering states and evanescent modes, leading to novel phenomena and a dual relation between conductance and charge accumulation.

Findings

Conductance depends on impurity strength and bias voltage.

Resonant backward scattering and perfect tunneling observed.

Dual relation between backscattered conductance and charge accumulation.

Abstract

We investigate transport through a single impurity in metallic zigzag carbon nanotube and find the conductance sensitively depends on the impurity strength and the bias voltage. It is rather interesting that interplay between the current-carrying scattering state and evanescent modes leads to rich phenomena including resonant backward scattering, perfect tunneling and charge accumulations. In addition, we also find a dual relation between the backscattered conductance and the charge accumulation. At the end, relevance to the experiments is discussed.