Tunable Fermi level and hedgehog spin texture in gapped graphene
10.1038/ncomms8610
Crossref journal-article
Springer Science and Business Media LLC
Nature Communications (297)
Abstract

AbstractSpin and pseudospin in graphene are known to interact under enhanced spin–orbit interaction giving rise to an in-plane Rashba spin texture. Here we show that Au-intercalated graphene on Fe(110) displays a large (∼230 meV) bandgap with out-of-plane hedgehog-type spin reorientation around the gapped Dirac point. We identify two causes responsible. First, a giant Rashba effect (∼70 meV splitting) away from the Dirac point and, second, the breaking of the six-fold graphene symmetry at the interface. This is demonstrated by a strong one-dimensional anisotropy of the graphene dispersion imposed by the two-fold-symmetric (110) substrate. Surprisingly, the graphene Fermi level is systematically tuned by the Au concentration and can be moved into the bandgap. We conclude that the out-of-plane spin texture is not only of fundamental interest but can be tuned at the Fermi level as a model for electrical gating of spin in a spintronic device.

Bibliography

Varykhalov, A., Sánchez-Barriga, J., Marchenko, D., Hlawenka, P., Mandal, P. S., & Rader, O. (2015). Tunable Fermi level and hedgehog spin texture in gapped graphene. Nature Communications, 6(1).

Authors 6
  1. A. Varykhalov (first)
  2. J. Sánchez-Barriga (additional)
  3. D. Marchenko (additional)
  4. P. Hlawenka (additional)
  5. P. S. Mandal (additional)
  6. O. Rader (additional)
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Dates
Type When
Created 10 years, 1 month ago (July 27, 2015, 6:08 a.m.)
Deposited 2 years, 7 months ago (Jan. 5, 2023, 6:16 a.m.)
Indexed 1 week ago (Aug. 27, 2025, 12:26 p.m.)
Issued 10 years, 1 month ago (July 27, 2015)
Published 10 years, 1 month ago (July 27, 2015)
Published Online 10 years, 1 month ago (July 27, 2015)
Funders 0

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@article{Varykhalov_2015, title={Tunable Fermi level and hedgehog spin texture in gapped graphene}, volume={6}, ISSN={2041-1723}, url={http://dx.doi.org/10.1038/ncomms8610}, DOI={10.1038/ncomms8610}, number={1}, journal={Nature Communications}, publisher={Springer Science and Business Media LLC}, author={Varykhalov, A. and Sánchez-Barriga, J. and Marchenko, D. and Hlawenka, P. and Mandal, P. S. and Rader, O.}, year={2015}, month=jul }