Mode localization analysis and characterization in a 5-beam array of coupled nearly identical micromechanical resonators for ultra-sensitive mass detection and analyte identification

Abstract

The use of vibration mode localization in arrays of micro-mechanically coupled, nearly identical beam-shaped resonators has been studied for ultrasensitive mass detection and analyte identification. Eigenstate shifts (amplitude shift in this work) that are three to four times (compared to single resonator), and orders (compared to resonator array) of magnitude greater than corresponding shifts in resonant frequency for an induced mass perturbation are theoretically analyzed, from the view points of geometrical design of the coupling overhang. A mechanically coupled beam-shaped 5-resonator array was therefore analyzed, fabricated, and characterized. The analytical results show that higher amplitudes could be obtained for the two outermost resonators due to the symmetrical design, while the empirical results show that high amplitude could only be obtained for one outermost resonator.