Vibrational characterization of high-Q silicon resonators for investigating thermal noise statistical properties

Silicon MEMS technology permits to develop high-Q resonators at the millimeter scale that can be used for the investigation of thermal noise statistical properties. In this paper we present a new design of a silicon torsional oscillator that we have named Quad Paddle Oscillator for the investigation of thermal noise in non-thermodynamic equilibrium due to steady-state thermal gradient. We evaluate its elastic response at room temperature and the Q-factor from room to cryogenic temperatures. With this resonator we find out that its elastic response depends only on average temperature defined as the volume-weighted mean of the temperatures of the respective elastic sections, regardless of whether a thermal gradients exists and its magnitude. This preliminary result opens a way for studying vibrational system out of equilibrium.