A New Paradigm to Half-Metallicity in Graphene Nanoribbons

Jin Yu; Wanlin Guo

doi:10.1021/jz4001328

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arXiv · 1304.3572

A New Paradigm to Half-Metallicity in Graphene Nanoribbons

Jin Yu·Wanlin Guo

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Abstract

In contrast to the well recognized transverse-electric-field-induced half-metallicity in zigzag graphene nanoribbons, here we demonstrate by first-principles calculations that zigzag graphene nanoribbons sandwiched between hexagonal boron nitride nanoribbons or sheets can be tuned into half-metal simply by a bias voltage or a moderate compressive strain. The half-metallicity is attributed to an enhanced coupling effect of spontaneous polarization and asymmetrical exchange correlation along the ribbon width. The findings should open a viable route for efficient spin-resolved band engineering in graphene based devices that are compatible with the current technology of semiconductor industry.

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Jin Yu, Wanlin Guo. 2013-04-12. A New Paradigm to Half-Metallicity in Graphene Nanoribbons. https://doi.org/10.1021/jz4001328

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