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

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.