Effective Screening of Localized Charged Perturbations in Metallic Nanotubes: Roles of Massive Bands

TL;DR

This paper investigates how massive electronic bands influence the screening of localized charges in metallic nanotubes, revealing effective screening lengths and the cancellation effects of massive bands, which are crucial for nanoscale device integration.

Contribution

It provides a theoretical comparison of continuous and lattice models to understand the role of massive bands in charge screening in metallic nanotubes.

Findings

Screening length is about the nanotube diameter.

Massive bands' effects are canceled by their interactions.

Good agreement between different theoretical approaches.

Abstract

The massive-band effects on screening behavior of metallic carbon nanotubes are theoretically investigated using two different methods; continuous and lattice quantum theories. Both approaches show screening of a localized external perturbation with an effective screening length of the order of the nanotube diameter. Calculating the nonlinear deformation of the local density of states near the charged perturbation, we show that the perturbative effects of the massive bands are effectively canceled by direct massive band interactions, such that a good agreement between the two methods can be achieved. The effective screening is important in nanoscale integration of nanotube-based electronic devices.