Mode Localization and Tunable Overlap in a Closed-Chain Micromechanical Resonator Array

Abstract

Figure 1: (a) Diagram of a 3-resonator closed-chain array. Inset: Cross-section of device layers. (b) Optical micrograph of a fabricated array. Inset: Electrical connections for the drive and coupling voltages.with a few exceptions [9][10][11].Here, we present a new design for resonator arrays that combines piezoelectric actuation and sensing with electrostatic coupling. This results in large vibration amplitudes that are transduced with high sensitivity while also having continuous coupling tunability. In addition, the array is coupled in a closed chain rather than a linear chain, where the last resonator in the chain is coupled back to the first resonator, as described in the next section. As a demonstration of the dynamic behavior of this array, two complementary schemes for tuning the coupling are implemented and the resulting amplitude and resonance frequency behaviors are presented. Finally, feedback control on an individual resonator is shown to be an effective approach for inducing mode localization and may be useful for optimizing the array's sensitivity to external perturbations.