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

TL;DR

This paper investigates how surface roughness scattering affects the quality factor of shear horizontal surface acoustic waves in nanoresonators, highlighting the importance of roughness parameters in dissipation.

Contribution

It provides a quantitative analysis of roughness-induced dissipation, emphasizing the role of roughness exponent and amplitude in nanoresonator quality factors.

Findings

Quality factors are comparable to intrinsic dissipation for H>0.5.

Surface roughness significantly impacts wave dissipation at certain wave vectors.

Design considerations must include roughness effects to optimize nanoresonator performance.

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.