Frequency readout of nanomechanical graphene drums via a microwave resonator coupling method

In this paper a novel microwave method with the capability of simultaneous actuation and readout of nano-mechanical resonators is described along with the fabrication of graphene nano-mechanical resonator sensor structures. The method uses a high Q quarter wave coaxial resonator coupled to a sharpened conductive tip to create a highly localised near field. Hence allowing for high sensitivity displacement measurements via measurement of changes in the resonant frequency of the coaxial resonator and a simultaneous driving force through a mutual capacitance between probe tip a conducting mechanical resonator. We discuss the use of the microwave system to measure monolayer graphene mechanical resonators and achieve readout of a resonant mode in a 3μm suspended graphene drum.