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arXiv · 1205.3923

Valley and spin polarization from graphene line defect scattering

Daniel Gunlycke·Carter T. White
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Abstract

Quantum transport calculations describing electron scattering off an extended line defect in graphene are presented. The calculations include potentials from local magnetic moments recently predicted to exist on sites adjacent to the line defect. The transmission probability is derived and expressed as a function of valley, spin, and angle of incidence of an electron at the Fermi level being scattered. It is shown that the previously predicted valley polarization in a beam of transmitted electrons is not significantly influenced by the presence of the magnetic moments. These moments, however, do introduce some spin polarization, in addition to the valley polarization, albeit no more than about 20%.

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Daniel Gunlycke, Carter T. White. 2012-05-17. Valley and spin polarization from graphene line defect scattering. https://doi.org/10.1116/1.4706892

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