Electromechanical transducers at the nanoscale: Actuation and sensing of motion in nanoelectromechanical systems (NEMS)

Electromechanical devices are rapidly being miniaturized, following the trend in commercial transistor electronics. Miniature electromechanical devices-now with dimensions in the deep sub-micrometer range-are envisioned for a variety of applications as well as for accessing interesting regimes in fundamental physics. Among the most important technological challenges in the operation of these nanoelectromechanical systems (NEMS) are the actuation and detection of their sub-nanometer displacements at high firequencies. In this Review, we shall focus on this most central concern in NEMS technology: realization of electromechanical transducers at the nanoscale. The currently available techniques to actuate and detect NEMS motion are introduced, and the accuracy, bandwidth, and robustness of these techniques are discussed.