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arXiv · 1101.2948

A spin-filter device based on armchair graphene nanoribbons

A. Saffarzadeh·R. Farghadan
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Abstract

The coherent spin-polarized electron transport through a zigzag-edge graphene flake (ZGF), sandwiched between two semi-infinite armchair graphene nanoribbons, is investigated by means of Landauer-Buttiker formalism. To study the edge magnetism of the ZGF, we use the half-filled Hubbard model within the Hartree-Fock approximation. The results show that the junction acts as a spin filter with high degree of spin polarization in the absence of magnetic electrodes and external fields. By applying a gate voltage the spin-filtering efficiency of this device can be effectively controlled and the spin polarization can reach values as high as 90%.

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A. Saffarzadeh, R. Farghadan. 2011-01-15. A spin-filter device based on armchair graphene nanoribbons. https://doi.org/10.1063/1.3537965

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