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arXiv · 0808.0401

Quality factor due to roughness scattering of shear horizontal surface acoustic waves in nanoresonators

G. Palasantzas
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Abstract

In this work we study the quality factor associated with dissipation due to scattering of shear horizontal surface acoustic waves by random self-affine roughness. It is shown the quality factor is strongly influenced by both the surface roughness exponent H, and the roughness amplitude w to lateral correlation length X ratio. Indeed, quality factors for roughness exponents H>0.5 are comparable to quality factors due to intrinsic dissipation mechanisms (e.g., thermoelastic losses and phonon-phonon scattering) especially for wave vectors <1/X. Our results indicate that this dissipation mechanism should be carefully considered in the design micro/nanoelectromechanical systems.

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G. Palasantzas. 2008-08-04. Quality factor due to roughness scattering of shear horizontal surface acoustic waves in nanoresonators. https://doi.org/10.1063/1.2977681

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