Graphene audio voltage amplifier.

The main building block of analog electronics is a voltage amplifier: an electronic device capable of amplifying small alternating current (AC) voltage signals. Many graphene analog electronic devices, performing different functions, 1-5 have recently been proposed stemming from high carrier mobility 6,7 and ambipolar transport in graphene field effect transistors (FETs). However, none of these devices was capable of signal amplification, thus ultimately requiring integration with Si transistors for performing this most important task. Here we demonstrate an integrated graphene voltage amplifier paving the way for all graphene analog electronics. 8