A Comprehensive Categorization of Micro/Nanomechanical Resonators and Their Practical Applications from an Engineering Perspective: A Review

Micro/nanoelectromechanical systems (M/NEMS), especially micro/nanomechanical resonators, provide an unprecedented platform for investigating a wide range of applications in both fundamental physical phenomena (such as quantum-level problems) and engineering and applied sciences (like sensing physical quantities and signal processing). In sensing context, these tiny resonators are invaluable tools for detecting weak forces and single molecules. Measuring such small variations in sub-nanometer amplitudes at high frequencies has created many practical challenges. Therefore, maximizing the responsivity to a specified input parameter and minimizing the responsivity to other inputs such as noise are considered as the optimal design for the excellent performance in nanoresonators. The present review aims to summarize some of the recent progress in this rapidly advancing field. Specifically, more attention is paid to the topics related to the dynamical behaviors of micro/nanoresonator and their practical applications. First, the theory behind micro/nanoresonators is described. Then a summary is presented of the basic concepts in resonant devices. In addition, several commonly dynamical techniques to enhance sensitivity are introduced. Finally, the devices are classified based on linear and nonlinear, single and array, symmetric and asymmetric, and frequency shift-based and amplitude shift-based resonators, along with the relative advantages and disadvantages of each one in engineering applications.