Nonlinear forced vibration of bilayer van der Waals materials drum resonator

摘要

The interlayer shear effect could play a crucial role in the dynamic behaviors of the nanoelectromechanical system (NEMS) resonators based on multilayer van der Waals (vdW) materials. However, the interlayer shear effect is rarely considered in the nonlinear forced vibrations of this kind of resonators. In this study, the nonlinear static and dynamics behaviors of drum resonators based on double layer MoS_2 (DLMoS_2) are investigated using molecular dynamics simulations and a nonlinear circular sandwich plate model (NCSPM), respectively. The interlayer shear effect and the geometrical nonlinearity are systematically considered in the NCSPM. Our results show that comparing with drum resonators based on single layer MoS_2 (SLMoS_2), the DLMoS_2 drum resonators exhibit higher fundamental frequency. The load-deflection curve of DLMoS_2 shows clear hardening-type nonlinearity, and the deflections of DLMoS_2 are smaller than that of SLMoS_2 under the same uniform load per layer. In particular, both frequency sweep excitation simulations and the NCSPM show that the hardening-type nonlinearity of the DLMoS_2 drum resonators is largely reduced due to the interlayer shear effect. Furthermore, DLMoS_2 with different twist angle exhibits different interlayer shear strengths; thus, the nonlinear characteristic could be controlled by changing the twist angles in the DLMoS_2 drum resonators. The present study should be of great help for designing NEMS resonators based on such vdW materials.