Utilizing Energy Localization in Weakly Coupled Nonlinear Resonators for Sensing Applications

In this paper, energy localization within weakly coupled nonlinear MEMS resonators has been utilized for sensing applications. The sensitivity and the noise floor of the weakly coupled resonators operating beyond the critical amplitude have been characterized at the boundaries of the unstable branch, termed as bifurcation points in this paper. The measurement results show that such measurements can provide beneficial gains in resolution when compared with linear operation, despite the reduced sensitivity at the top bifurcation point. A minimum input-referred noise floor of 18 ppb/Hz ^1/2 has been achieved through this sensing scheme which is a 40 % betterment in comparison to its linear counterpart.