Splitting of vibration mode in an imperfect submicron circular plate

The dynamics of micro-/nanoscale plates are extremely sensitive to external conditions. Here, the vibration of a submicron-thick circular plate exposed to its ambient environment was investigated. The obtained results indicate that the vibration behavior of circular plates shows a strong dependence on the surrounding conditions. Mode pair splitting was observed in a vibration experiment. One crucial influence factor is the asymmetry due to exposure to an ambient environment. Therefore, numerical analyses were performed to identify the vibration of a circular plate due to symmetry breaking. A detailed finite element analysis revealed that symmetry breaking can lead not only to the splitting of some pairs of modes but also to shifts in natural frequencies. In addition, the relationships between the asymmetry and the frequency shift were identified together with the differences in the mode pairs for the circular plates. This study should be of great help for understanding the vibration of submicron plates and the design of submicron-scale resonators and biological sensors.