Ohmic electromechanical dissipation in nanomechanical cantilevers

We study the contribution of ohmic dissipation to the mechanical damping of nanoresonators. This damping occurs when DC voltage is applied to a resistive resonator, because the mechanical motion modifies the associated capacitance, thus inducing a dissipative current. Silicon carbide nanowire resonators were studied as a function of applied voltage and their geometrical environment. Nanometric positioners were used to control and continuously modify the position of the resonator with respect to counter electrodes. The experimental results are shown to be in agreement with an electromechanical model developed here, which allows for the establishment of a universal formula for the lower dissipation limit of a nanoresonator in its capacitive environment.