Table of Contents Author Guidelines Submit a Manuscript
Advances in Condensed Matter Physics
Volume 2014 (2014), Article ID 370619, 6 pages
http://dx.doi.org/10.1155/2014/370619
Research Article

Determination of the DC Electrical Conductivity of Multiwalled Carbon Nanotube Films and Graphene Layers from Noncontact Time-Domain Terahertz Measurements

1Optoelectronics and Laser Technology Group (GOTL), Carlos III de Madrid University, Leganes, 28911 Madrid, Spain
2IMEP-LAHC, UMR CNRS 5130, University of Savoy, 73376 Le Bourget du Lac Cedex, France

Received 22 January 2014; Accepted 15 March 2014; Published 7 April 2014

Academic Editor: Veer P. S. Awana

Copyright © 2014 E. Dadrasnia et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Measuring the DC conductivity of very thin films could be rather difficult because of the electrical contact issue. This DC conductivity can, however, be extracted from noncontact measurements at GHz and THz frequencies using elaborated conductivity models that nicely fit the experimental data. Here we employ this technique to study the DC conductivity of fragile nanometer-thick films of multiwalled carbon nanotubes and monolayer graphene. The THz response of the films is measured by THz time-domain spectroscopy. We show that the THz conductivity of the samples is well fitted by either Drude-Lorentz model or Drude-Smith model, giving information on the physics of electrical conductivity in these materials. This extraction procedure is validated by the good agreement between the so-obtained DC conductivity and the one measured with a classical 4-point probe in-line contact method.