Tuning mechanical modes and influence of charge screening in nanowire resonators

Abstract

We probe electromechanical properties of InAs nanowire (diameter ∼100 nm) resonators where the suspended nanowire is also the active channel of a field-effect transistor. We observe and explain the nonmonotonic dispersion of the resonant frequency with dc gate voltage (V_g^dc). The effect of electronic screening on the properties of the resonator can be seen in the amplitude. We observe the mixing of mechanical modes with V_g^dc. We also experimentally probe and quantitatively explain the hysteretic nonlinear properties, as a function of V_g^dc, of the resonator using the Duffing equation.