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arXiv · 1601.02445

Theory of electronic and spin-orbit proximity effects in graphene on Cu(111)

Tobias Frank·Martin Gmitra·Jaroslav Fabian
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Abstract

We study orbital and spin-orbit proximity effects in graphene adsorbed to the Cu(111) surface by means of density functional theory (DFT). The proximity effects are caused mainly by the hybridization of graphene $\pi$ and copper d orbitals. Our electronic structure calculations agree well with the experimentally observed features. We carry out a graphene-Cu(111) distance dependent study to obtain proximity orbital and spin-orbit coupling parameters, by fitting the DFT results to a robust low energy model Hamiltonian. We find a strong distance dependence of the Rashba and intrinsic proximity induced spin-orbit coupling parameters, which are in the meV and hundreds of $\mu$eV range, respectively, for experimentally relevant distances. The Dirac spectrum of graphene also exhibits a proximity orbital gap, of about 20 meV. Furthermore, we find a band inversion within the graphene states accompanied by a reordering of spin and pseudospin states, when graphene is pressed towards copper.

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Tobias Frank, Martin Gmitra, Jaroslav Fabian. 2016-01-11. Theory of electronic and spin-orbit proximity effects in graphene on Cu(111). https://doi.org/10.1103/physrevb.93.155142

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