Spin-Polarized Electrons in Bilayer Graphene Flakes

P. A. Orellana; L. Rosales; L. Chico; M. Pacheco

doi:10.1063/1.4809752

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arXiv · 1301.4974

Spin-Polarized Electrons in Bilayer Graphene Flakes

P. A. Orellana·L. Rosales·L. Chico·M. Pacheco

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Abstract

We show that a bilayer graphene flake deposited above a ferromagnetic insulator can behave as a spin-filtering device. The ferromagnetic material induces exchange splitting in the graphene flake, and due to the Fano antiresonances occurring in the transmission of the graphene flake as a function of flake length and energy, it is possible to obtain a net spin current. This happens when an antiresonance for one spin channel coincides with a maximum transmission for the opposite spin. We propose these structures as a means to obtain spin-polarized currents and spin filters in graphene-based systems.

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P. A. Orellana, L. Rosales, L. Chico, M. Pacheco. 2013-01-21. Spin-Polarized Electrons in Bilayer Graphene Flakes. https://doi.org/10.1063/1.4809752

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