Conductance and mobility in suspended graphene as a function of charge density. (a) Mobility versus charge density for suspended (red line) and nonsuspended (black line) graphene at = 100 K. The blue line represents the ballistic model prediction. Inset: schematic representation of the suspended graphene device [96]. (b) Conductance versus gate voltage (at = 40 K) for a suspended graphene device before (blue line) and after (red line) annealing and current-induced cleaning. The red dotted line was calculated using a ballistic model. Inset: AFM image of the suspended graphene device [89].
