Tunable Attenuator based on commercial graphene nanoplatelets

A series tunable graphene attenuator based on commercially acquired graphene nanoplatelets is presented. The attenuator is composed of a microstrip line with a gap. Graphene nanoplatelets are drop-casted in the gap. The transmission scattering parameters can be modified by a bias voltage supplied to the graphene nanoplatelets. Even though the resistance of commercially acquired graphene cannot be brought down beyond a specific value, yet the structure is designed to alter the resistance variation in a desirable range. The resulting dynamic range of transmission is comparable to a similar structure designed by lab grown graphene nanoplatelets. A prototype is fabricated and the simulated results are verified through experiments. The attenuator works from 1 GHz to 10 GHz with a maximum tunable range of up to 10 dB.