Role of covalent and metallic intercalation on the electronic properties of epitaxial graphene on SiC(0001)

Abstract

We present an orbital-resolved density functional theory study on the electronic properties of hydrogen and lithium intercalated graphene grown on the Si face of SiC. Starting from the $(6\sqrt{3}\times 6\sqrt{3})R30^{\circ }$ surface reconstruction of the graphene/SiC heterosystem, we find that both H and Li can restore the ideal structural characteristics of the two nonequivalent junction parts (i.e. graphene and the SiC substrate) when inserted at the interface. However, the chemical/electrostatic interactions remain different for the two cases. Hence, H-intercalated epitaxial graphene is subject to a sublattice symmetry-breaking electronic interference that perturbs the Dirac point, whereas Li intercalation gives rise to a highly $n$-doped system due to a nonuniform delocalization of Li charges. Results bring to discussion the role of substrate engineering in epitaxial graphene on SiC.

6 pages, 4 figures, accepted in PRB

References in corpus (10)

• The electronic properties of graphene
• Substrate-induced band gap opening in epitaxial graphene
• Ab initio Study of Graphene on SiC
• Origins of anomalous electronic structures of epitaxial graphene on silicon carbide
• Understanding adsorption of hydrogen atoms on graphene
• The quasi-free-standing nature of graphene on H-saturated SiC(0001)
• Highly p-doped graphene obtained by fluorine intercalation
• Wafer-scale Epitaxial Graphene Growth on the Si-face of Hexagonal SiC (0001) for High Frequency Transistors
• Electronic structure of epitaxial graphene nanoribbons on SiC(0001)
• Single-layer metallicity and interface magnetism of epitaxial graphene on SiC(000$\bar{1}$)

Cited by in corpus (5)

• Li-intercalated Graphene on SiC(0001): an STM study
• Observation of the quantum Hall effect in epitaxial graphene on SiC(0001) with oxygen adsorption
• Electron backscattering from stacking faults in SiC by means of \textit{ab initio} quantum transport calculations
• Revealing the nature of defects in quasi free standing mono-layer graphene on SiC(0001) by means of Density Functional Theory
• Intrinsic structural and electronic properties of the Buffer Layer on Silicon Carbide unraveled by Density Functional Theory