Finite Size Effect on Nanomechanical Mass Detection: Role of Surface Elasticity

Finite Size Effect on Nanomechanical Mass Detection: Role of Surface Elasticity

Mai Duc Dai, Chang-Wan Kim, and Kilho Eom 

Abstract

Nanomechanical resonators have recently been highlighted because of their remarkable ability to perform the sensing and detection. Since the nanomechanical resonators arecharacterized by large surface-to-volume ratio, it is implied that the surfaceeffect plays a substantial role on not only the resonance but also the sensing performance of nanomechanical resonators. In this work, we have studied therole of surface effect on the detection sensitivity of a nanoresonator that undergoes either harmonic vibration or nonlinear oscillation based on the continuum elastic model such as an elastic beam model. It is shown that surface effect makes an impact on both harmonic resonance and nonlinear oscillations, and that the sensing performance is dependent on the surface effect. Moreover,we have also investigated the surface effect on the mechanical tuning of resonance and sensing performance. It is interestingly found that the mechanical tuning of resonance is independent of surface effect, while the mechanical tuning of sensing performance is determined by surface effect. Our study shedslight on the importance of surface effect on the sensing performance of nanoresonators. 

This manuscript will appear in Nanotechnology.