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arXiv · 1008.3189

Magnetic exchange mechanism for electronic gap opening in graphene

T. G. Rappoport·M. Godoy·B. Uchoa·R. R dos Santos·A. H. Castro Neto
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Abstract

We show within a local self-consistent mean-field treatment that a random distribution of magnetic adatoms can open a robust gap in the electronic spectrum of graphene. The electronic gap results from the interplay between the nature of the graphene sublattice structure and the exchange interaction between adatoms.The size of the gap depends on the strength of the exchange interaction between carriers and localized spins and can be controlled by both temperature and external magnetic field. Furthermore, we show that an external magnetic field creates an imbalance of spin-up and spin-down carriers at the Fermi level, making doped graphene suitable for spin injection and other spintronic applications.

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T. G. Rappoport, M. Godoy, B. Uchoa, R. R dos Santos, A. H. Castro Neto. 2011-10-08. Magnetic exchange mechanism for electronic gap opening in graphene. https://doi.org/10.1209/0295-5075%2F96%2F27010

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