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arXiv · 0904.3315

Band-structure topologies of graphene: spin-orbit coupling effects from first principles

M. Gmitra·S. Konschuh·C. Ertler·C. Ambrosch-Draxl·J. Fabian
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Abstract

The electronic band structure of graphene in the presence of spin-orbit coupling and transverse electric field is investigated from first principles using the linearized augmented plane-wave method. The spin-orbit coupling opens a gap at the $K(K')$-point of the magnitude of 24 $μ$eV (0.28 K). This intrinsic splitting comes 96% from the usually neglected $d$ and higher orbitals. The electric field induces an additional (extrinsic) Bychkov-Rashba-type splitting of 10 $μ$eV (0.11 K) per V/nm, coming from the $σ$-$π$ mixing. A 'mini-ripple' configuration with every other atom is shifted out of the sheet by less than 1% differs little from the intrinsic case.

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M. Gmitra, S. Konschuh, C. Ertler, C. Ambrosch-Draxl, J. Fabian. 2009-07-23. Band-structure topologies of graphene: spin-orbit coupling effects from first principles. https://doi.org/10.1103/physrevb.80.235431

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