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arXiv · 1112.2159

Adatoms in graphene as a source of current polarization: Role of the local magnetic moment

Matheus P. Lima·Antônio J. R. da Silva·A. Fazzio
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Abstract

We theoretically investigate spin-resolved currents flowing in large-area graphene, with and without defects, doped with single atoms of noble metals (Cu, Ag and Au) and 3d-transition metals (Mn,Fe,Co and Ni). We show that the presence of a local magnetic moment is a necessary but not sufficient condition to have a non zero current polarization. An essential requirement is the presence of spin-split localized levels near the Fermi energy that strongly hybridize with the graphene pi-bands. We also show that a gate potential can be used to tune the energy of these localized levels, leading to an external way to control the degree of spin-polarized current without the application of a magnetic field.

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Matheus P. Lima, Antônio J. R. da Silva, A. Fazzio. 2011-12-09. Adatoms in graphene as a source of current polarization: Role of the local magnetic moment. https://doi.org/10.1103/physrevb.84.245411

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