Fabrication and measurement of graphene p–n junction with two top gates

A graphene device with two top gates has been fabricated and measured for the first time. The thickness of the gate dielectric is 60 nm. The measurement results indicate that the externally applied gate biases can dope the underneath graphene to either p- or n-type, forming an induced p-n junction. The current-voltage (I-V) curve measurement results also indicate that there is no nonlinear phenomenon in a weakly induced graphene p-n junction. This graphene p-n junction can potentially be used for terahertz wave generation.