Theory 17/Nanomechanics

Dissipation Is a Surface Ratio

The claim

Dissipation in nanomechanical resonators is set by the ratio of surface loss to volume loss, so shrinking a device increases loss even in the same material.

01The mechanism

Energy is lost at surfaces and interfaces; as the device shrinks, the surface contributes a larger share of the stored elastic energy, so the quality factor falls.

02Predictions

P1Quality factor should fall as surface-to-volume rises.
P2Surface treatments should shift the loss.

03Refutation

Quality factor independent of surface-to-volume would remove the surface mechanism.