Electronic structure and band-gap modulation of graphene via substrate surface chemistry

We have studied the electronic structure of graphene deposited on a SiO2 surface using density functional methods. The band structure of the graphene monolayer strongly depends on surface characteristics of the underlying SiO2 surface; for an oxygen-terminated surface, the monolayer exhibits a finite energy band gap while the band gap is closed when the oxygen atoms on the substrate are passivated with hydrogen atoms. We find that at least a graphene bilayer is required for a near zero energy gap when deposited on a substrate without H-passivation. Our results are discussed in the light of recent experiments.

[1]  Georg Kresse,et al.  Norm-conserving and ultrasoft pseudopotentials for first-row and transition elements , 1994 .

[2]  Roger E Bumgarner,et al.  Benzene Forms Hydrogen Bonds with Water , 1992, Science.

[3]  G. Kresse,et al.  Ab initio molecular dynamics for liquid metals. , 1993 .

[4]  Andre K. Geim,et al.  Two-dimensional atomic crystals. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[5]  K Schulten,et al.  VMD: visual molecular dynamics. , 1996, Journal of molecular graphics.

[6]  P. Hohenberg,et al.  Inhomogeneous Electron Gas , 1964 .

[7]  Alexander Mattausch,et al.  Ab initio study of graphene on SiC. , 2007, Physical review letters.

[8]  P. Kim,et al.  Energy band-gap engineering of graphene nanoribbons. , 2007, Physical review letters.

[9]  Fujita,et al.  Edge state in graphene ribbons: Nanometer size effect and edge shape dependence. , 1996, Physical review. B, Condensed matter.

[10]  C Berger,et al.  Electronic structure of epitaxial graphene layers on SiC: effect of the substrate. , 2007, Physical review letters.

[11]  E. Williams,et al.  Atomic structure of graphene on SiO2. , 2007, Nano letters.

[12]  G. Kresse,et al.  Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set , 1996 .

[13]  W. Kohn,et al.  Self-Consistent Equations Including Exchange and Correlation Effects , 1965 .

[14]  D. Vanderbilt,et al.  Soft self-consistent pseudopotentials in a generalized eigenvalue formalism. , 1990, Physical review. B, Condensed matter.

[15]  Louis E. Brus,et al.  High-resolution scanning tunneling microscopy imaging of mesoscopic graphene sheets on an insulating surface , 2007, Proceedings of the National Academy of Sciences.

[16]  Kresse,et al.  Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. , 1996, Physical review. B, Condensed matter.

[17]  H. Dai,et al.  Chemically Derived, Ultrasmooth Graphene Nanoribbon Semiconductors , 2008, Science.

[18]  A. V. Fedorov,et al.  Substrate-induced bandgap opening in epitaxial graphene. , 2007, Nature materials.

[19]  Oded Hod,et al.  Electronic structure and stability of semiconducting graphene nanoribbons. , 2006, Nano letters.

[20]  S. Louie,et al.  Energy gaps in graphene nanoribbons. , 2006, Physical Review Letters.

[21]  S. Pantelides,et al.  Encapsulation of floating carbon nanotubes in SiO(2). , 2006, Physical review letters.

[22]  Graphene-on-Sapphire and Graphene-on-Glass: Raman Spectroscopy Study , 2007, 0710.2369.

[23]  J. Lyding,et al.  Characterization of nanometer-sized, mechanically exfoliated graphene on the H-passivated Si(100) surface using scanning tunneling microscopy , 2007, Nanotechnology.

[24]  J. Rogers,et al.  Guided growth of large-scale, horizontally aligned arrays of single-walled carbon nanotubes and their use in thin-film transistors. , 2005, Small.

[25]  M. I. Katsnelson,et al.  On the roughness of single- and bi-layer graphene membranes , 2007, cond-mat/0703033.

[26]  T. Ohta,et al.  Controlling the Electronic Structure of Bilayer Graphene , 2006, Science.

[27]  K. Novoselov.  Graphene: mind the gap. , 2007, Nature materials.

[28]  Aachen,et al.  A Graphene Field-Effect Device , 2007, IEEE Electron Device Letters.

[29]  Andre K. Geim,et al.  Electric Field Effect in Atomically Thin Carbon Films , 2004, Science.

[30]  A. Zunger,et al.  Self-interaction correction to density-functional approximations for many-electron systems , 1981 .

[31]  C. Hierold,et al.  Spatially resolved Raman spectroscopy of single- and few-layer graphene. , 2006, Nano letters.

[32]  Philip Kim,et al.  Electronic transport in locally gated graphene nanoconstrictions , 2007 .

[33]  C. Keast,et al.  Epitaxial Graphene Transistors on SiC Substrates , 2008, IEEE Transactions on Electron Devices.

[34]  G. Kresse,et al.  From ultrasoft pseudopotentials to the projector augmented-wave method , 1999 .

[35]  Blöchl,et al.  Projector augmented-wave method. , 1994, Physical review. B, Condensed matter.

[36]  M. Rooks,et al.  Graphene nano-ribbon electronics , 2007, cond-mat/0701599.

[37]  F. Guinea,et al.  Biased bilayer graphene: semiconductor with a gap tunable by the electric field effect. , 2006, Physical review letters.

[38]  P. Ajayan,et al.  Energy gaps in zero-dimensional graphene nanoribbons , 2007 .