Optical response of finite-length carbon nanotubes

TL;DR

This paper investigates the optical properties of finite-length metallic carbon nanotubes, revealing that the fundamental plasmon resonance remains stable while higher-frequency resonances shift due to edge charge effects.

Contribution

It provides a self-consistent calculation of the optical response including edge charges, highlighting the robustness of the fundamental plasmon mode in finite nanotubes.

Findings

Fundamental plasmon resonance is unaffected by edge charges.

Higher-frequency resonances shift to higher frequencies.

Edge charge effects are rapidly screened inside the nanotube.

Abstract

Optical response of finite-length metallic carbon nanotubes is calculated including effects of induced edge charges in a self-consistent manner. The results show that the main resonance corresponding to excitation of the fundamental plasmon mode with wave vector $\pi/l$ with $l$ being the tube length is quite robust and unaffected. This arises because the strong electric field associated with edge charges is screened and decays rapidly inside the nanotube. For higher-frequency resonances, the field starts to be mixed and tends to shift resonances to higher frequencies.