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arXiv · 0903.2602

Defect scattering in graphene

Jian-Hao Chen·W. G. Cullen·C. Jang·M. S. Fuhrer·E. D. Williams
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Abstract

Irradiation of graphene on SiO2 by 500 eV Ne and He ions creates defects that cause intervalley scattering as evident from a significant Raman D band intensity. The defect scattering gives a conductivity proportional to charge carrier density, with mobility decreasing as the inverse of the ion dose. The mobility decrease is four times larger than for a similar concentration of singly charged impurities. The minimum conductivity decreases proportional to the mobility to values lower than 4e^2/(pi*h), the minimum theoretical value for graphene free of intervalley scattering. Defected graphene shows a diverging resistivity at low temperature, indicating insulating behavior. The results are best explained by ion-induced formation of lattice defects that result in mid-gap states.

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Jian-Hao Chen, W. G. Cullen, C. Jang, M. S. Fuhrer, E. D. Williams. 2009-03-15. Defect scattering in graphene. https://doi.org/10.1103/physrevlett.102.236805

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