Operation of Graphene Transistors at GHz Frequencies
  Top-gated graphene transistors operating at high frequencies (GHz) have been fabricated and their characteristics analyzed. The measured intrinsic current gain shows an ideal 1/f frequency dependence, indicating an FET-like behavior for graphene transistors. The cutoff frequency fT is found to be proportional to the dc transconductance gm of the device. The peak fT increases with a reduced gate length, and fT as high as 26 GHz is measured for a graphene transistor with a gate length of 150 nm. The work represents a significant step towards the realization of graphene-based electronics for high-frequency applications. 
Yu-Ming Lin, Keith A. Jenkins, Alberto Valdes-Garcia, Joshua P. Small,   Damon B. Farmer, and Phaedon Avouris