Dynamics of NEMS resonators across dissipation limits

The oscillatory dynamics of nanoelectromechanical systems (NEMS) is at the heart many emerging applications in nanotechnology. For common NEMS, such as beams and strings, formulated using a dissipationless wave equation derived from elasticity. Under harmonic ansatz, gives an undamped free vibration equation; solving this with proper boundary conditions provides eigenfunctions familiar standing patterns. Any harmonically driven solution expressible terms these eigenfunctions. Here, we show that formalism becomes inconvenient dissipation increases. To end, experimentally map out position- frequency-dependent motion NEMS string resonator linearly by non-symmetric force on one end different limits. At low (high Q factor), observe sharp resonances patterns closely match string. With slight increase dissipation, become lost waves begin to propagate along nanostructure. large (low propagating strongly attenuated display little, if any, resemblance A more efficient intuitive description can be obtained superposition