Intrinsic bilayer graphene is a semimetal. Upon applying an electric field, the potential
difference between top and bottom layers can open an energy gap and tune bilayer
graphene to an insulating state at the charge neutrality point. Here, we demonstrate that the
properties of semimetallic bilayer graphene can be controllably tuned to either metallic or
insulating by a simple way of iodine molecular doping. The transport properties of iodine-
doped bilayer graphene have been systematically investigated. At high iodine doping …