Formation of Subgap States in Carbon Nanotubes Due to a Local Transverse Electric Field

Loading...
Thumbnail Image
Penn collection
Department of Physics Papers
Degree type
Discipline
Subject
Physical Sciences and Mathematics
Physics
Funder
Grant number
License
Copyright date
Distributor
Related resources
Author
Kinder, Jesse M.
Contributor
Abstract

We introduce two simple models to study the effect of a spatially localized transverse electric field on the low-energy electronic structure of semiconducting carbon nanotubes. Starting from the Dirac Hamiltonian for the low-energy states of a carbon nanotube, we use scattering theory to show that an arbitrarily weak field leads to the formation of localized electronic states inside the free nanotube band gap. We study the binding energy of these subgap states as a function of the range and strength of the electrostatic potential. When the range of the potential is held constant and the strength is varied, the binding energy shows crossover behavior: the states lie close to the free nanotube band edge until the potential exceeds a threshold value, after which the binding energy increases rapidly. When the potential strength is held constant and the range is varied, we find resonant behavior: the binding energy passes through a maximum as the range of the potential is increased. Large electric fields confined to a small region of the nanotube are required to create localized states far from the band edge.

Advisor
Date Range for Data Collection (Start Date)
Date Range for Data Collection (End Date)
Digital Object Identifier
Series name and number
Publication date
2007-11-27
Journal title
Volume number
Issue number
Publisher
Publisher DOI
Journal Issue
Comments
Suggested Citation: Kinder, J.M. and Mele, E.J. (2007). Formation of subgap states in carbon nanotubes due to a local transverse electric field. Physical Review B. 76, 195438. © 2007 The American Physical Society http://dx.doi.org/10.1103/PhysRevB.76.195438
Recommended citation
Collection