▎ 摘　　要

A dual-gate graphene field-effect transistor is presented, which shows improved radio-frequency (RF) performance by reducing the access resistance using electrostatic doping. With a carrier mobility of 2700 cm(2)/V . s, a cutoff frequency of 50 GHz is demonstrated in a 350-nm-gate-length device. This f(T) value is the highest frequency reported to date for any graphene transistor, and it also exceeds that of Si MOS field-effect transistors at the same gate length, illustrating the potential of graphene for RF applications.