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arXiv · 0906.3809

Wavevector-dependent spin filtering and spin transport through magnetic barriers in graphene

L. Dell'Anna·A. De Martino
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Abstract

We study the spin-resolved transport through magnetic nanostructures in monolayer and bilayer graphene. We take into account both the orbital effect of the inhomogeneous perpendicular magnetic field as well as the in-plane spin splitting due to the Zeeman interaction and to the exchange coupling possibly induced by the proximity of a ferromagnetic insulator. We find that a single barrier exhibits a wavevector-dependent spin filtering effect at energies close to the transmission threshold. This effect is significantly enhanced in a resonant double barrier configuration, where the spin polarization of the outgoing current can be increased up to 100% by increasing the distance between the barriers.

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L. Dell'Anna, A. De Martino. 2009-06-20. Wavevector-dependent spin filtering and spin transport through magnetic barriers in graphene. https://doi.org/10.1103/physrevb.80.155416

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