Viscous damping of nanobeam resonators: Humidity, thermal noise, and a paddling effect

Abstract

A nanobeam resonator is a key mechanical component of a nano-electromechanical system. Because of its small dimensions, the system can reach very high frequencies, but it is also very sensitive to its environment, as a large surface area of the material is exposed. Molecular dynamics (MD) simulations and theoretical analysis are used here to quantitatively predict the damping behavior of a nanobeam, including its critical damping conditions and lifetime, directly mapping fluid-structure properties and interaction into dynamics. We show here how the humidity defines the critical damping condition through viscous forces, marking the transition from the under-damping to the over-damping regime ..