Suppression of spin polarization in graphene nanoribbons by edge defects and impurities
نویسندگان
چکیده
We investigate the effect of edge defects vacancies and impurities substitutional dopants on the robustness of spin polarization in graphene nanoribbons GNRs with zigzag edges by using density-functionaltheory calculations. The stability of the spin state and its magnetic moments is found to continuously decrease with increasing the concentration of the defects or impurities. The system generally becomes nonmagnetic at the concentration of one edge defect impurity per 10 Å. The spin suppression is shown to be caused by the reduction and removal of edge states at the Fermi energy. Our analysis implies an important criterion on the GNR samples for spintronics applications.
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