Linear sensing for mode-localized sensors

The sensitivity of the resonant sensors has been proven to be enhanced by more than two orders of magnitude using mode localization of the weakly coupled resonators as the sensing mechanism. The amplitude-related metrics such as amplitude ratios are generally elected as the readout for the mode-localized sensors which is different from the traditional resonant sensors using frequency readouts. However, linear sensing across the veering point is still under-investigation due to the inherent loci veering phenomenon. This paper proposes that linear sensing across the veering point can be realized by selecting amplitude difference as an output metric while driving all the resonators simultaneously. It is also found that the linear sensing range of the amplitude difference readout seamlessly connects with that of the amplitude ratio readout. By adaptively selecting the proper output metrics, continuous linear sensing in full scale is realized.