Thermal Energy Loss Mechanisms in Micro- to Nano-scale Devices

In micro- and nano-scale resonators, a key performance metric is the quality factor (Q), which is the ratio of stored mechanical energy to the energy dissipated. In well-optimized designs, Q is limited by thermal physics and specific energy loss mechanisms including thermoelastic, Akhieser, and Landau-Rumer damping. The relative importance of each effect depends on the time and length scales dominating the device. Most published analyses focus on special regimes where only one mechanism dominates, though real devices may operate in regimes that are not the limiting case. This paper presents thermal damping across the range of frequency and length scales. Data on acoustic loss is compared with theory.