Effects of environmental and exciton screening in single-walled carbon nanotubes

TL;DR

This paper investigates how environmental and exciton screening influence the exciton binding energy in single-walled carbon nanotubes, aligning theoretical estimates with experimental data to better understand their electronic properties.

Contribution

It introduces a detailed analysis of screening effects on exciton binding energies in SWCNTs, improving theoretical predictions to match experimental observations.

Findings

Screening significantly reduces exciton binding energy in SWCNTs.

Theoretical estimates align well with experimental data.

Environmental factors play a crucial role in exciton behavior.

Abstract

The ground-state exciton binding energy for single-walled carbon nanotubes (SWCNTs) in vacuum calculated ignoring the screening of Coulomb interaction appears to be much greater than the corresponding band gap. The most essential contributions to the screening of electron-hole (e-h) interaction potential in semiconducting SWCNTs, which return the ground-state exciton binding energy into the energy gap, are considered. Our estimates on the screening effects and exciton binding energies are in satisfactory agreement with the corresponding experimental data for concrete nanotubes.