▎ 摘　　要

We use a combination of charge writing and scanning gate microscopy to map and modify the local charge neutrality point of graphene field-effect devices. We give a demonstration of the technique by writing remote charge in a thin dielectric layer over a graphene-metal interface and detecting a shift in the local charge neutrality point. We perform electrostatic simulations to characterize the interaction between a realistic scanning probe tip, the deposited charge, and the graphene and find a good semi-quantitative agreement with the experimental results. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4732802]