H S Skulason et al 2010 Nanotechnology 21 295709 doi:10.1088/0957-4484/21/29/295709
H S Skulason, P E Gaskell and T Szkopek
Show affiliationsThe optical reflection contrast and optical transmission contrast of graphitic films on glass ranging in thickness from a monolayer to the limit of bulk graphite have been experimentally measured. For samples with more than 10 graphene layers where optical contrast quantization becomes difficult to observe, atomic force microscopy was used to measure the sample thickness. The visible optical reflection and transmission of thin graphitic films is found to depend strongly on the real component of the optical conductance per graphene layer, and comparatively weakly on the imaginary component of optical conductance. This observation in part explains the significant variation in the refractive index of graphene and graphite reported in the literature to date. Spectroscopic measurements reveal a strong dispersion in the optical conductance of even a 10 layer film, consistent with an imaginary conductance arising from virtual transitions at the band edges of the π and σ bands at the M and Γ points, respectively.
Issue 29 (23 July 2010)
Received 17 February 2010, in final form 28 May 2010
Published 5 July 2010
H S Skulason et al 2010 Nanotechnology 21 295709
Andrzej Grzechnik et al 2007 J. Phys.: Condens. Matter 19 266219
J M Posse et al 2011 J. Phys.: Condens. Matter 23 215401
Damien P George 2010 J. Phys.: Conf. Ser. 259 012034
Andrew Nelson 2010 J. Phys.: Conf. Ser. 251 012094
Alexander W. Blocker et al. 2009 ApJ 701 1742
Ian J. M. Crossfield et al. 2010 ApJ 723 1436
S A Sandersius et al 2011 Phys. Biol. 8 045008
: from surface reconstructions to carbon electronics