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arXiv · 0910.4043

Spin Valve Effect in ZigZag Graphene Nanoribbons by Defect Engineering

Sankaran Lakshmi·Stephan Roche·Gianaurelio Cuniberti
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Abstract

We report on the possibility for a spin valve effect driven by edge defect engineering of zigzag graphene nanoribbons. Based on a mean-field spin unrestricted Hubbard model, electronic band structures and conductance profiles are derived, using a self-consistent scheme to include gate-induced charge density. The use of an external gate is found to trigger a semiconductor-metal transition in clean zigzag graphene nanoribbons, whereas it yields a closure of the spin-split bandgap in the presence of Klein edge defects. These features could be exploited to make novel charge and spin based switches and field effect devices.

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Sankaran Lakshmi, Stephan Roche, Gianaurelio Cuniberti. 2009-10-21. Spin Valve Effect in ZigZag Graphene Nanoribbons by Defect Engineering. https://doi.org/10.1103/physrevb.80.193404

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