Transparent microwave absorber based on single layer graphene film

High quality single layer graphene grown by chemical vapor deposition (CVD) method has sheet impedance ranging from 300 ohm to 600 ohm. We demonstrate that it can be used as an absorbing film in Salisbury absorber. An efficient and accurate transmission line model is proposed for such transparent graphene film absorber at 38.5 GHz. Result of transmission line model is in good agreement with that of the 3D full-wave simulation. Finally, the sample of the graphene absorber is fabricated, and an easy-to-use testing method based on pyramidal horn antenna is proposed to characterize the absorbing property of the absorber sample.