  Surface roughness influences significantly the quality factor of high
frequency nanoresonators for large frequency - relaxation times within the
non-Newtonian regime, where a purely elastic dynamics develops. It is shown
that the influence of sort wavelength roughness, which is expressed by the
roughness exponent H for the case of self-affine roughness, plays significant
role in comparison with the effect of the long wavelength roughness parameters
such as the rms roughness amplitude and the lateral roughness correlation
length. Therefore, the surface morphology can play important role in designing
high-frequency resonators operating within the non-Newtonian regime.
