AVS 58th Annual International Symposium and Exhibition
    Graphene and Related Materials Focus Topic Tuesday Sessions
       Session GR+EM-TuM

Paper GR+EM-TuM5
Infrared Optical Conductance of CVD-grown Graphene

Tuesday, November 1, 2011, 9:20 am, Room 208

Session: Graphene: Optical Properties, Optoelectonics and Photonics
Presenter: J.W. Weber, Eindhoven University of Technology, Netherlands
Authors: J.W. Weber, Eindhoven University of Technology, Netherlands
M.C.M. van de Sanden, Eindhoven University of Technology, Netherlands
Correspondent: Click to Email

The infrared optical conductance of chemical vapour deposited (CVD) graphene is determined from near normal incidence reflection and transmission Fourier transform infrared measurements in the spectral range of 370-7000 cm-1. The real part of the conductance, up to 2500 cm-1 , shows both the effect from doping and finite temperature that was shown for exfoliated graphene.1,2 The conductance for the range 2500-7000 cm-1 is increasing from the value for the universal optical conductance (πe2/2h) to 1.5 times this value. This could imply that graphene and bilayer graphene have grown in a 1:1 ratio. The graphene is grown via CVD of methane and hydrogen on Cu-foil and transferred to a glass substrate following the procedure of Li et al.3 A three-phase optical model (air/graphene/glass) is used to simultaneously fit the reflection and transmission data and extract the (Kramers-Kronig consistent) optical conductance. The conductance will be used to compare it with the conductance of CVD-graphene that is exposed to a hydrogen plasma.

1Mak et al. Phys. Rev. Lett 101, 196405 (2008)

2Li et al. Nat. Phys. 4, 532 (2008)

3Li et al. Science 324, 1312 (2009)