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We report that the {pi}-electrons of graphene can be spin-polarized to create a phase with a significant spin-orbit gap at the Dirac point (DP) using a graphene-interfaced topological insulator hybrid material. We have grown epitaxial Bi2Te2Se (BTS) films on a chemical vapor deposition (CVD) graphene. We observe two linear surface bands both from the CVD graphene notably flattened and BTS coexisting with their DPs separated by 0.53 eV in the photoemission data measured with synchrotron photons. We further demonstrate that the separation between the two DPs, {Delta}D-D, can be artificially fine-tuned by adjusting the amount of Cs atoms adsorbed on the graphene to a value as small as {Delta}D-D = 0.12 eV to find any proximity effect induced by the DPs. Our density functional theory calculation shows a spin-orbit gap of ~20 meV in the {pi}-band enhanced by three orders of magnitude from that of a pristine graphene, and a concomitant phase transition from a semi-metallic to a quantum spin Hall phase when {Delta}D-D $leq$ 0.20 eV. We thus present a practical means of spin-polarizing the {pi}-band of graphene, which can be pivotal to advance the graphene-based spintronics.
We review progress in developing epitaxial graphene as a material for carbon electronics. In particular, improvements in epitaxial graphene growth, interface control and the understanding of multilayer epitaxial graphenes electronic properties are di
The effect of oxygen adsorption on the local structure and electronic properties of monolayer graphene grown on SiC(0001) has been studied by means of Low Energy Electron Microscopy (LEEM), microprobe Low Energy Electron Diffraction (muLEED) and micr
We demonstrate that electronic and magnetic properties of graphene can be tuned via proximity of multiferroic substrate. Our first-principles calculations performed both with and without spin-orbit coupling clearly show that by contacting graphene wi
We investigate the interactions between two identical magnetic impurities substituted into a graphene superlattice. Using a first-principles approach, we calculate the electronic and magnetic properties for transition-metal substituted graphene syste
Graphene has shown great application potentials as the host material for next generation electronic devices. However, despite its intriguing properties, one of the biggest hurdles for graphene to be useful as an electronic material is its lacking of