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arXiv · 1105.0139

Viscous damping of nanobeam resonators: humidity, thermal noise and the paddling effect

Chao Chen·Ming Ma·Jefferson Zhe Liu·Quanshui Zheng·Zhiping Xu
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Abstract

The nanobeam resonator is the key mechanical component in the nano-electromechanical system. In addition to its high frequency originating from its low dimension, the performance is significantly influenced by the circumstances, especially at nanoscale where a large surface area of the material is exposed. Molecular dynamics simulations and theoretical analysis are used for a quantitative prediction on the damping behavior, such as the critical damping condition and lifetime, of nanobeam resonators that directly maps the fluid-structure properties and interaction information into dynamical behaviors. We show here how the humidity defines the critical damping condition through viscous forces, marking the transition from under-damping to over-damping regime at elevated humidity. Novel phenomena such as the thermal fluctuation and paddling effects are also discussed.

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Chao Chen, Ming Ma, Jefferson Zhe Liu, Quanshui Zheng, Zhiping Xu. 2011-05-01. Viscous damping of nanobeam resonators: humidity, thermal noise and the paddling effect. https://doi.org/10.1063/1.3619854

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