  Nanomechanical resonators have recently been highlighted because of their
remarkable ability to perform the sensing and detection. Since the
nanomechanical resonators are characterized by large surface-to-volume ratio,
it is implied that the surface effect plays a substantial role on not only the
resonance but also the sensing performance of nanomechanical resonators. In
this work, we have studied the role 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 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,
and that the mechanical tuning of sensing performance is determined by surface
effect. Our study sheds light on the importance of surface effect on the
sensing performance of nanoresonators.
