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arXiv · 0906.5604

Magnetism of Substitutional Co Impurities in Graphene: Realization of Single $π$-Vacancies

E. J. G. Santos·D. Sanchez-Portal·A. Ayuela
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Abstract

We report {\it ab initio} calculations of the structural, electronic and magnetic properties of a graphene monolayer substitutionally doped with Co (Co$_{sub}$) atoms. We focus in Co because among traditional ferromagnetic elements (Fe, Co and Ni), only Co$_{sub}$ atoms induce spin-polarization in graphene. Our results show the complex magnetism of Co substitutional impurites in graphene, which is mapped into simple models such as the $π$-vacancy and Heisenberg model. The links established in our work can be used to bring into contact the engineering of nanostructures with the results of $π$-models in defective graphene. In principle, the structures considered here can be fabricated using electron irradiation or Ar$^+$ ion bombardment to create defects and depositing Co at the same time.

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E. J. G. Santos, D. Sanchez-Portal, A. Ayuela. 2009-06-30. Magnetism of Substitutional Co Impurities in Graphene: Realization of Single $π$-Vacancies. https://doi.org/10.1103/physrevb.81.125433

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