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arXiv · 1008.4387

Colossal negative magnetoresistance in dilute fluorinated graphene

X. Hong·S. -H. Cheng·C. Herding·J. Zhu
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Abstract

Adatoms offer an effective route to modify and engineer the properties of graphene. In this work, we create dilute fluorinated graphene using a clean, controlled and reversible approach. At low carrier densities, the system is strongly localized and exhibits an unexpected, colossal negative magnetoresistance. The zero-field resistance is reduced by a factor of 40 at the highest field of 9 T and shows no sign of saturation. Unusual "staircase" field dependence is observed below 5 K. The magnetoresistance is highly anisotropic. We discuss possible origins, considering quantum interference effects and adatom-induced magnetism in graphene.

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X. Hong, S. -H. Cheng, C. Herding, J. Zhu. 2010-08-25. Colossal negative magnetoresistance in dilute fluorinated graphene. https://doi.org/10.1103/physrevb.83.085410

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