Home

About

Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network
FAQHELPSITE MAPCONTACT US


  Advanced Search  

 
Effect of scattering and contacts on current and electrostatics in carbon nanotubes A. Svizhenko* and M. P. Anantram
 

Summary: Effect of scattering and contacts on current and electrostatics in carbon nanotubes
A. Svizhenko* and M. P. Anantram
Center for Nanotechnology and NASA Advanced Supercomputing Division, NASA Ames Research Center,
Mail Stop: 229-1 Moffett Field, California 94035-1000, USA
Received 23 December 2004; published 12 August 2005
We computationally study the electrostatic potential profile and current carrying capacity of carbon nano-
tubes as a function of length and diameter. Our study is based on solving the nonequilibrium Green's function
and Poisson equations self-consistently, including the effect of electron-phonon scattering. A transition from
the ballistic to diffusive regime of electron transport with an increase of applied bias is manifested by quali-
tative changes in the potential profiles, differential conductance, and electric field in a nanotube. In the low-bias
ballistic limit, most of the applied voltage drop occurs near the contacts. In addition, the electric field at the
tube center increases proportionally with diameter. In contrast, at high biases, most of the applied voltage drops
across the nanotube, and the electric field at the tube center decreases with an increase in diameter. We find that
the differential conductance can increase or decrease with bias as a result of an interplay of nanotube length,
diameter, and a quality factor of the contacts. From an application viewpoint, we find that the current carrying
capacity of nanotubes increases with an increase in diameter. Finally, we investigate the role of inner tubes in
affecting the current carried by the outermost tube of a multiwalled nanotube.
DOI: 10.1103/PhysRevB.72.085430 PACS number s : 72.10. d, 73.23.Ad, 73.63.Fg, 73.63.Nm
I. INTRODUCTION
Metallic carbon nanotubes are near-ideal conductors of

  

Source: Anantram, M. P. - Department of Electrical Engineering, University of Washington at Seattle

 

Collections: Materials Science; Computer Technologies and Information Sciences